Eaton Cutler-Hammer Digitrip 1150 User manual

Effective 10/2004
Page 1I.L. 70C1036H05 I.L. 70C1036H05
Table of Contents
1.0 GeneralDescriptionofDigitripTripUnits ................. 7
1.1 Protection ............................................................... 7
1.2 ModeofTripandStatusInformation ........................ 7
1.3 InstallationandRemoval.......................................... 7
1.3.1 InstallationoftheTripUnit ............................ 7
1.3.2 RatingPlugInstallation ................................. 8
1.3.3 TripUnit/RatingPlugRemoval....................... 9
1.4 Wiring ..................................................................... 9
1.5 Plexiglass Cover ..................................................... 9
1.6 DT1150Power/RelayModule.................................. 9
1.6.1 AuxiliaryPower............................................. 9
1.6.2 Alarm Contacts............................................. 9
1.7 Standards.............................................................. 10
2.0 Description of Magnum CircuitBreakers ............... 10
2.1 General ................................................................. 10
2.2 Low-EnergyTripActuator ...................................... 11
2.3 GroundFaultProtection ........................................ 11
2.3.1 General....................................................... 11
2.3.2 Residual Sensing (3 Wire or 4 Wire) ........... 12
2.3.3 SourceGroundSensing.............................. 12
2.3.4 ZeroSequence Sensing.............................. 12
2.3.5 MultipleSource/MultipleGround ................. 12
2.3.6 GroundFaultSettings................................. 12
2.4 Current Sensors for Standard Breaker .................. 13
2.5 Current Sensors for Double Wide Breaker ............ 13
3.0 PrinciplesofOperation .......................................... 13
3.1 General ................................................................. 13
3.2 TripandOperation Indicators................................. 13
3.2.1 Status/Long Pickup LED............................. 13
3.2.2 AlarmLED.................................................. 14
3.2.3 TripLED ..................................................... 14
3.3 Making Current Release ........................................ 14
3.4 ZoneInterlocking ................................................... 14
3.5 PTModule ............................................................ 14
4.0 Programming/ViewingDigitrip1150 ....................... 19
4.1 MainMenu ............................................................ 19
4.1.1 PowerUp Sequence ................................... 19
4.1.2 PushbuttonDefinition.................................. 19
4.1.3 BlinkMode ................................................. 22
4.1.4 Programming/ViewingScreens ................... 22
4.1.5 ResetPushbuttonOperation(AfterTrip) ..... 22
4.2 Program Settings PGM SET ................................. 22
4.2.1 CURRENTCurveTypeSelection and
Pickup/TimeSettings ................................. 22
4.2.2 VOLTAGE - Frequency,ReversePower .... 26
4.2.3 INCOM Communications .......................... 28
4.2.4 Aux RELAYS.............................................. 28
4.2.5 ALARMS .................................................... 28
4.2.6 Digital RelayAccessory Module ................. 28
4.2.7 TripLink....................................................... 30
4.2.8 SettingTIME............................................... 31
4.2.9 Selecting DISPLAYS .................................. 31
4.2.10 SYSTEM Settings ...................................... 31
4.3 View Settings (VIEW SET).................................... 31
4.3.1 FirmwareMenu ........................................... 31
4.4 METERMenu ....................................................... 31
4.5 HARMONICMenu ................................................. 32
4.6 EventLOG ............................................................. 32
4.7 PowerandEnergyParameters.............................. 32
4.8 Power Quality ....................................................... 33
4.8.1 PowerFactor,THDandCrestFactor .......... 33
4.8.2 Alarms........................................................ 33
4.9 WAVEFORMCAPTURE Feature .......................... 33
4.9.1 SixCycleWaveformCaptureonTrip........... 33
4.9.2 OneCycle WaveformCapture ..................... 33
4.10 HEALTH ................................................................ 33
5.0 TestProcedures .................................................... 34
5.1 General ................................................................. 34
5.2 When to Test ........................................................ 34
5.2.1 SelfTesting................................................. 34
5.2.2 FunctionalFieldTesting .............................. 35
5.3 PerformanceTestingfor Ground FaultTrip Units.... 35
5.3.1 CodeRequirements .................................... 35
5.3.2 StandardRequirements .............................. 36
5.3.3 GeneralTestInstructions ............................ 36
6.0 Battery .................................................................. 37
6.1 General ................................................................. 37
6.2 Battery Test .......................................................... 37
6.3 Battery Installation and Removal ........................... 37
7.0 FrameRatings
(SensorRatingsandRatingPlugs)........................ 38
8.0 RecordKeeping .................................................... 38
9.0 References............................................................ 39
9.1 Magnum and MagnumDSCircuitBreakers........... 39
9.2 Time-CurrentCurves.............................................. 39
AppendixA ZoneInterlockingExamples....................... 43
AppendixB TroubleshootingGuide ............................... 45
AppendixC Typical Breaker Master
ConnectionDiagram.............................................. 47
AppendixD DisplayMenuDiagrams............................. 48
AppendixE DisplayAbbreviations................................. 76
Appendix F Digitrip Settings and Descriptions.............. 78
Appendix G Auxiliary Relays........................................ 81
Appendix H Digital RelayAccessory Module................ 82
Appendix I Modbus Translator Wiring ........................ 83
Instructions for Digitrip Models 1150, 1150i and 1150+,
1150+iTrip Units for use only in Cutler-Hammer Magnum
and Magnum DS Circuit Breakers
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Effective 10/2004
Page 2 I.L. 70C1036H05
WARNING
DO NOTATTEMPT TO INSTALL OR PERFORM
MAINTENANCEONEQUIPMENT WHILE IT IS
ENERGIZED.DEATHOR SEVEREPERSONALINJURY
CANRESULT FROMCONTACTWITH ENERGIZED
EQUIPMENT.ALWAYS VERIFY THAT NO VOLTAGE IS
PRESENTBEFORE PROCEEDING.ALWAYS FOLLOW
SAFETYPROCEDURES. CUTLER-HAMMERIS NOT
LIABLE FOR THE MISAPPLICATION OR
MISINSTALLATION OF ITS PRODUCTS.
WARNING
OBSERVEALLRECOMMENDATIONS, NOTES,CAU-
TIONS,AND WARNINGS RELATING TO THE SAFETY
OFPERSONNELANDEQUIPMENT.OBSERVEAND
COMPLY WITHALL GENERALAND LOCAL HEALTH
ANDSAFETY LAWS, CODES,ANDPROCEDURES.
NOTE:The recommendations andinformationcontained
hereinarebasedonexperienceand judgement, but should
notbeconsidered to be all inclusive orto cover every
application or circumstance which may arise.
Figure1.1 Digitrip 1150 Catalog # 11PLSIG Trip Unit with Rating Plug
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Effective 10/2004
Page 3I.L. 70C1036H05
Table1.1a CURRENTProtection Functions for Digitrip 1150/1150iTrip
Notes: 1. ANSI/ULversions are limited to 1200Amperes to comply with ULand NEC standards.
2. Fourcauseof trip LEDs indicate LONG, SHORT, INSTor GROUND trip. Making CurrentRelease and the
separate High Instantaneous Module are indicated by the Instantaneous LED.
3. An additional setting is marked M1 where:
StandardCircuit Breaker M1 = 14 x Infor PlugAmps 100 through 1250A
M1 = 12 x Infor PlugAmps 1600, 2000, 2500A
M1 = 10 x Infor PlugAmps 3000, 3200A
DoubleWideCircuitBreaker M1 = 14 x Infor PlugAmps 2000, 2500A
M1 = 12 x Infor PlugAmps 3000, 3200, 4000, 5000A(see Section 2.5)
M1 = 10 x Infor PlugAmps 6000A, 6300A
4. OnlyavailablewhenLongTimeI2Tisselected.
5. Phase protection with 3 TRIP response types (See Section 4.2.1).
Trip Unit Type Digitrip 1150 Digitrip 1150i
Ampere Range 100A-6000A 200A-6300A
RMS Sensing Yes Yes
Protection and Coordination
Protection Ordering Options Catalog #
Fixed Rating Plug (In)
OverTEMPerature TRIP
Curve Type
SLOPE
11LSI, 11LSIG, 11LSIA or
11PLSI, 11PLSIG, 11PLSIA
Yes
Yes
LSI/LSIG, LSIA
I2T, I4T
IEEE5
11IEC, 11IEC-EF or
11PIEC, 11PIECEF
Yes
Yes
LSI/LSIG
I2T,I4T
IEC5
Long LONG delay Pick Up
Delay LONG delay TIME @ 6 x (Ir) I2T
Protection LONG delay TIME @ 6 x (Ir) I4T
LONG delay thermal MEMORY
0.4-1.0 x (In)
2-24 seconds
1-5 seconds
Yes
0.4-1.0 x (In)
2-24 seconds
1-5 seconds
Yes
SHORT delay Pick Up3
Short
Delay SHORT delay TIME @ 8 x (Ir) I2T4
Protection SHORT delay TIME FLAT
SHORT delay TIME ZONE INTERLOCK
150-1000% or 1200% or 1400%x
(Ir)
0.10-0.50 s
0.10-0.50 s
Yes
150-1000% or 1200% or 1400% x (Ir)
0.10-0.50 s
0.10-0.50 s
Yes
Instan- INSTantaneous Pick Up
taneous
Protection Off setting
Making Current Release
200-1000% x or 1200% or 1400%
(In)
Yes
Yes
200-1000% or 1200% or 1400% x (In)
Yes
Yes
Neutral 4th Pole or External Neutral Trip
Protection Yes-CAT # LSI only (50%,100%) Yes-CAT # IEC only (50%,100%)
Ground GROUND fault option
(Earth) GROUND fault Pick Up
Fault Off Position
Protection GROUND fault delay @ .625 x (In) I2T
GROUND fault delay FLAT
GROUND fault ZONE INTERLOCK
GROUND fault memory
Yes
24-100% x (In)1
No
0.10-0.50 s
0.10-0.50 s
Yes
Yes
Yes
10-100% x (In)
Yes
0.10-0.50 s
0.10-0.50 s
Yes
Yes
Phase Protection
AMP UNBALANCE
PHASE LOSS (current-based) Yes Yes Yes Yes
System Diagnostics / Protection Related Alarms
Status/Long Pick Up LED
Cause of Trip LED’s Yes Yes2Yes
Yes2
HighLOAD ALARM
Long Delay Pick Up ALARM
GROUND ALARM
GROUND ALARM only
NEUTral AMPere ALARM
OPeration COUNT ALARM
Yes
Yes
Yes-CAT # LSIG
Yes –CAT# LSIA
Yes
Yes
Yes
Yes
Yes- CAT# IECEF
–
Yes
Yes
Auxiliary Relay Contacts (Programmable)
Block Close (1 contact)
ALARM/TRIP (2 contacts) Yes Yes Yes Yes
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Effective 10/2004
Page 4 I.L. 70C1036H05
Table1.1bMetering Datafor Digitrip 1150/1150i Trip Units
Current Metering Units Tolerance Notes
IA, IB, IC, IN,
IG
IA, IB, IC (AVG)
IN,IG (AVG)
IA, IB, IC (Max)
IN,IG (Max)
IA, IB, IC (Min)
IN,IG (Min)
Amperes
Amperes
Amperes
Amperes
Amperes
Amperes
Amperes
Amperes
±1% FS
±2% FS
Real timedata, FS= In rating
Real timedata, FS= In rating
5 MINUTE AVERAGE
5 MINUTE AVERAGE
(Tolerance applicable for 5 to 100% of In
and current will startmetering@ .02 per unit)
Group values held until Reset.
Based onapproximately 1second
timeinterval
Voltage Metering
VAB,VBC, VCA Volts ±1% FS FS (Full Scale) =690 V
Power Metering
Power
kVA
kvar
DEMAND kW
DEMAND Max kW
DEMAND kVA
DEMAND Max kVA
kW
kVA
kvar
kW
kW
kVA
kVA
±2% FS
±2% FS
±2% FS
±2% FS
±2% FS
±2% FS
±2% FS
Approximately 1 second update
LASTAVG - 5 MININTERVAL
SLIDING or FIXED 15 MIN INTERVAL*
LASTAVG - 5 MININTERVAL
SLIDING or FIXED 15 MIN INTERVAL*
Energy Metering
ENERGY kWh
ENERGY Rev kWh
KVAh
kWh
kWh
kVAh
±2% FS
±2% FS
±2% FS
Metering Related Alarms
kVA DEMAND ALARM
kW DEMAND ALARM KVA kW 1 to 12500 1 to 12500 LASTAVG - 5 min fixed interval LASTAVG - 5 min fixed interval
Other
kVAh PULSE INITIATE
kWh PULSEINITIATE kVAh kWh See section
4.7 INITIATE is anabbreviation for INITIATOR
INITIATE is anabbreviationfor INITIATOR
* Only one of DEMAND MaxkW or DEMAND Max kVA can beSLIDING INTERVAL
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Effective 10/2004
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I.L. 70C1036H05
Table1.1cPower Quality Datafor Digitrip 1150/1150i Trip Units
Harmonic Units Notes
THD (Total Harmonic Distortion)
THDA
THDB
THDC
THDN
Per Harmonic Data
HARMON A
HARMON B
HARMON C
HARMON N
CF (Crest Factor)
CFA
CFB
CFC
CFN
0 to 99 percent
0 to 99 percent
0 to 99 percent
0 to 99 percent
0 to 99 percent
0 to 99 percent
0 to 99 percent
0 to 99 percent
1.0 to25.5
1.0 to25.5
1.0 to25.5
1.0 to25.5
Phase A current
Phase B current
Phase Ccurrent
Neutral current
Fundamental through 27th
Phase A current
Phase B current
Phase Ccurrent
Phase Ncurrent
Phase A current
Phase B current
Phase Ccurrent
Phase Ncurrent
Power Factor / Frequency
PF (Power Factor)
PF MIN
PFMAX
0 to 1.00
0 to 1.00
0 to 1.00
Located in METER menu, real time data
Value held until Reset
Value held until Reset
Hz (Frequency) Hz Located in METER menu
Power Quality Related Alarms (Programmable)
LOW PFALARM
THD ALARM 50 to 95 percent 10 to 30 percent OFF setting available OFF setting available
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Table1.1d VOLTAGE PROTECTIONfunctions for Digitrip 1150/1150iTripUnits
Trip Unit Type Digitrip 1150+Digitrip 1150i+
Ordering Catalog Number 11PLSI, 11PLSIG, 11PLSIA 11PIEC, 11PIECEF
SYSTEM Frequency 50 or 60 Hz 50 or 60 Hz
TRIPS
RANGE STEP SIZE TOLERANCE
UnderVoltage Trip 90 to 670 Volts 1 volt +/- 7 volts
UnderVoltageTime 1 to 250 seconds 1 second +2.5s, -0.5s or +2%, -2%
whichever is larger
OverVoltage Trip 180 to 720 Volts 1 volt +/- 7 volts
OverVoltageTime 1 to 250 seconds 1 second +2.5s, -0.5s or +2%, -2%
whichever is larger
UnderFrequency Trip 48 to 52 Hz(50 Hz)
58 to 62 Hz(60Hz) 0.1 Hz +/- .05 Hz
UnderFrequency Time 0.20 to 5.0 seconds 0.02 seconds +0.1s/-0s
OverFrequency Trip 48 to 52 Hz(50 Hz)
58 to 62 Hz(60Hz) 0.1 Hz +/- .05 Hz
OverFrequency Time 0.20 to 5.0 seconds 0.02 seconds +0.1s/-0s
Voltage Unbalance Trip 5% to 50% 1% +/-3
Voltage Unbalance Time 1 to 250 seconds 1 second +2.5s, -0.5s or +2%, -2%
whichever is larger
Reverse Power Trip 1 to 65000kW 1 kW +/- 2% FS
Reverse Power Time 1 to 250 seconds 1 second 0, +2%
+3s whicheveris larger
ALARMS
RANGE STEP SIZE TOLERANCE
UnderVoltage Alarm 90 to 670 Volts 1 volt +/- 7 volts
UnderVoltageAlarmTime 1 to 250 seconds 1 second +2.5s, -0.5s or +2%, -2%
whichever is larger
OverVoltage Alarm 180 to 720 Volts 1 volt +/- 7 volts
OverVoltage AlarmTime 1 to 250 seconds 1 second +2.5s, -0.5s or +2%, -2%
whichever is larger
UnderFrequency Alarm 48 to 52 Hz(50 Hz)
58 to 62 Hz(60Hz) 0.1 Hz +/- .05 Hz
UnderFrequency AlarmTime 0.20 to 5.0 seconds 0.02 seconds +0.1s/-0s
OverFrequency Alarm 48 to 52 Hz(50 Hz)
58 to 62 Hz(60Hz) 0.1 Hz +/- .05 Hz
OverFrequency AlarmTime 0.20 to 5.0 seconds 0.02 seconds +0.1s/-0s
Voltage Unbalance Alarm 5% to 50% 1% +/-3
Voltage Unbalance AlarmTime 1 to 250 seconds 1 second +2.5s, -0.5s or +2%, -2%
whichever is larger
Phase Rotation Alarm ABC, CBA, OFF - -
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Effective 10/2004
Page 7I.L. 70C1036H05
Ifyouhaveanyquestionsorneedfurtherinformationor
instructions,pleasecontact your local representative or
theCutlerHammerCustomerSupport Center.
1.0 GENERAL DESCRIPTION OF DIGITRIP TRIP UNITS
The Digitrip Trip Units are circuit breaker subsystems that
providetheprotectivefunctionsofacircuit breaker.The trip
unit is in a removable sealed housing, installed in the
circuit breaker, and can be replaced in the field by the end
user.
Thisinstruction book specifically covers the applicationof
Digitrip Trip Units, as illustrated in Figure 1.1, installed in
MagnumandMagnumDSBreakers.Throughoutthis
InstructionalLeaflet,the use of the term“MagnumBreak-
ers”refersto both the Magnum andMagnumDS low-
voltage,ACpowercircuitbreakers.
The Magnum Digitrip line of trip units consists of the 1150
whichconforms to ULstandards,and model 1150icon-
formingtoIECstandards.ThroughoutthisInstructional
Leaflet, the use of the term Digitrip 1150 trip units refers to
both models unless otherwise stated.
The Digitrip 1150 trip units may be applied to either 50 or
60 Hz systems.
DigitripDT1150 familyoftrip unitsincorporate two micro-
processorsintheir design. One processor isdevoted
totally to the task of current protection functions. This
processorprovidestrueRMScurrentsensingfortheproper
coordinationwiththe thermal characteristics of conductors
andequipment.TheDigitripanalyzes the secondary
currentsignals from the circuit breakercurrent sensors
and,when preset current levels and time delay settings are
exceeded, sends an initiating trip signal to the TripActua-
torofthecircuit breaker.The current sensorsprovide
operating power to the trip unit.As current begins to flow
through the circuit breaker, the sensors generate a sec-
ondarycurrent which powers the trip unit.
Thesecondmicroprocessor provides the voltage protection
display, communications, metering, harmonic calcula-
tions,alarmingand auxiliary relay functions. These
additionalfeaturesrequire that auxiliary power beprovided
to the circuit breaker.
1.1 Protection
EachDigitripDT1150TripUnitis completely self-contained
andrequires no external control power to operate its basic
overcurrentprotectionfunctions.Itoperatesfromcurrent
signallevelsderivedthroughcurrentsensors mounted in
thecircuitbreaker.The types of protection availablefor
eachmodel are shown inTable 1.1.
TheDigitrip1150family of tripunitsprovides five phase and
twoground(time-current) curve-shaping adjustments.To
satisfy the protection needs of any specific installation, the
exactselection of the availableprotection function is
adjustable.Theshortdelayand ground fault adjustments
includeeithera FLATor I2Tresponse.Apictorial represen-
tationofthe applicable time-current curves for the selected
protectionfunctionsisprovided,foruserreference,onthe
face of the trip unit as shown in Figure 1.1.
NOTE:The Digitrip 1150 (11LSI ,11PLSI style) andDigitrip
1150i (11IEC, 11PIEC) are the styles that can be used on
3-poleor4-pole circuit breakers for theprotectionof the
neutral circuit. For a 3-pole circuit breaker an external
sensor of the same rating as the phase sensor needs
wired to the circuit breaker. Only these styles can provide
neutralprotection, although all styles can provide neutral
metering and alarming (one exception is that there is no
meteringforsourceorzerosequenceGroundFault
application).These styles also have aprotection setting
called Neutral Ratio. The 100% setting is the default and
isused when phase andneutral conductors are of the
same ampacity. The 50% setting is for a half sized neutral
conductorand essentually shifts the Long Timethermal
curve to the left making it more sensitive. Refer to the
NationalElectricCode(NEC)fortheappropriateapplica-
tionfor4-pole circuit breakers.
1.2 Mode of Trip and Status Information
Onall DT1150units,agreen light emitting diode(LED),
labeled Status, blinks approximately once each second to
indicate that the trip unit is operating normally. This Status
LED will blink at a faster rate if the Digitrip is in a pick-up,
oroverload, mode.
Red LEDs on the face of the 1150 family of trip units flash
to indicate the cause, or trip mode, for an automatic trip
operation(forexample, ground fault, overload, or short
circuit trip).A battery in the Digitrip unit maintains the trip
indication until the Reset button is pushed. The battery is
satisfactory if its LED lights green when the Battery Test
button is pushed (See Section 6).
NOTE:The Digitrip 1150 family provides all protection
functions regardless of the status of the battery. The
battery is only needed to maintain the automatic trip
indicationon the mimic curve of the Digitrip when auxiliary
powerisnotavailable.
1.3 Installation and Removal
1.3.1 Installation of the Trip Unit
Align the Digitrip unit with the molded guide ears on the
platformand springclipsofthe Magnum Circuit Breaker.
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Beforeplugginginto the black edge connector,align the
long pins on the bottom of the Digitrip into the white, I1,
connector (See Figure 1.2). Press the unit into circuit
breakeruntilthe PC board edge engages intotheconnector
andthespring clips engage over the Digitrip’s housing.
NOTE: Recheck visually the connector I1 to insure all plugs
areengaged properly.
1.3.2 Rating Plug Installation
WARNING
DONOT ENERGIZETHE MAGNUMCIRCUIT BREAKER
WITHTHE DIGITRIP REMOVED ORDISCONNECTED
FROMITS CONNECTOR. DAMAGE TOINTERNAL
CURRENTTRANSFORMERS MAYOCCURDUE TOAN
Figure 1.2 Installation of the Digitrip Unit into a Magnum Circuit Breaker (Side View)
OPENCIRCUIT CONDITION. THERE IS NO PROTEC-
TION FOR THE LOAD CIRCUIT.
CAUTION
IFA RATING PLUG IS NOT INSTALLED IN THE TRIP
UNIT, THE UNIT WILL INITIATE A TRIP WHEN IT IS
ENERGIZED.INADDITIONTHE INSTANTANEOUS LED
WILL LIGHT ON A PLUG TRIP.
Insert the rating plug into the cavity on the right-hand side
of the trip unit.Align the three pins on the plug with the
sockets in the cavity. The plug should fit with a slight
insertionforce.
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Toremove the trip unit from the circuitbreaker, deflect the
top and bottom spring clips to release the unit from the
black mounting platform. Pull the unit to disengage the trip
unit’s printed circuit board connectors J0 & I1 from the
circuitbreaker(See Figure 1.2 and Appendix C).
1.4 Wiring
Theinternalcomponents of the circuit breaker and their
connection points to the secondary contacts, are shown in
thebreakermasterconnection diagram provided on page
47 asAppendix C.
1.5 Plexiglass Cover
Aclear, tamper-proof plexiglass door sits on the circuit
breakercover.This door, if sealed, allows the settings to
beviewedbutnotchanged, except by authorized person-
nel.Theplexiglasscover meets applicable tamper-proof
requirements.Thecoveris held in place by two cover
screws. Security is insured by the insertion of a standard
meterseal through the holes in bothof the cover retention
screws. The plexiglass cover has an access cutout for the
View Functions group of pushbuttons and the BatteryTest
pushbutton.
1.6 DT 1150 Power/Relay Module
ThePower/RelayModule(SeeFigure 1.4) is a standard
deviceforthe Digitrip 1150model.Themoduleis installed
onthe molded platform under the trip unit in the Magnum
CircuitBreaker. There are four style modules thatcover
thefollowinginput voltageratings: 120 VAC, 230VAC,24-
48VDCand 125 VDC (100-140 VDCoperatingrange).The
burden of the Power/Relay Module is 10VA. Check circuit
breakercoverlabelmarkingfor proper trip unit power and
voltagerating.
1.6.1 Auxiliary Power
Whenthemodule is wired and supplied withproper
voltage,it will providean auxiliary powersupply so that the
DT1150’s(LED) display will be functional even when the
circuit breaker has no load.ADigitrip 1150 unit without
auxiliarypowerwillnotprovide voltage, display any data or
communicate.
1.6.2 Alarm Contacts
A second function of this module is to provide either a trip
or alarmoutput contact via the twocustomer programmed
relays within the module.An assortment of relay functions
can be assigned to these relays. (See the Aux Relay
programminginAppendixD-15 and Appendix G). Each
relay is a normally open contact with a programming
identification of RELAYAand RELAY C. On the Breaker
MasterConnection Diagram (Appendix C) these contacts
Figure 1.3 Installation of the Rating Plug and Mounting
Screw
CAUTION
DO NOT FORCE THE RATING PLUG INTO THE CAVITY.
Use a 1/8" (3 mm) wide screwdriver to tighten the M4
screw and secure the plug and the trip unit to the circuit
breaker(See Figure1.3).Close the rating plug door.
CAUTION
THEM4 SCREW SHOULD BE TIGHTENED ONLYUNTIL
IT IS SNUG. DO NOT USEA LARGE SCREWDRIVER.A
1/8" (3 mm) WIDE SCREWDRIVER BLADE IS AD-
EQUATE.
1.3.3 Trip Unit/Rating Plug Removal
Toremove the ratingplug from the trip unit, openthe rating
plugdoor. Use a 1/8" (3 mm)wide screwdriver to loosen
the M4 screw. Pull the door to aid in releasing the rating
plugfrom the unit.
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Figure1.4 Power/RelayModulefor1150 TripUnit
arelabeledATR_Alarm andATR_latch.TheATR_latch is a
latching relay that will hold contact status even if auxiliary
power is lost to the circuit breaker. This relay does require
auxiliarypowerfor resetting. The resetting of theserelays
requiresdepressingtheRESETpushbuttononthefront
panelof the Digitrip 1150.
1.6.2.1 GroundAlarm
Agroundfaultalarmis one of many possible programmable
alarmsandcanprovideanearlywarningofagroundfault
conditioninprogressvia an alarm LED.
Inaddition, this unit can be programmed toenergize an
alarm relay upon this condition. The alarm relay will reset
automatically if the ground current is less than the ground
alarm pickup setting.
On the LSIAstyle unit, a redALARM ONLY LED (See
Figure 3.3) willindicate the presence ofgroundfault
current, when it is in excess of GROUND PICKUP setting.
Ground tripping will not occur with the LSIA style unit.
1.6.2.2 Block Close Relay
Also in this module is a relay that can block the remote
closing of a circuit breaker after a trip condition. This Block
functionis enabled by programming theAux RelayB via
thefrontpanelorviaPowerNetcommunication(See
AppendixD-15).Theblock close function can be further
setupfor“AUTO” or “MANUAL” resetviaprogramming
(11Pxxx only). This trip condition requires a front panel
reset to clear the Block Close condition.
1.7 Standards
TheDigitrip1150TripUnitsarelisted by the Underwriters
Laboratories,Inc.®, UL File E52096, foruse in Magnum
CircuitBreakers.Thesedeviceswere tested to theANSI
C37.13breakerstandardandANSIC37.17tripunit
standard.Additionally, these same units are also listed by
theCanadianStandardsAssociation (CSA) under file LR
43556.
All Digitrip units have also passed the IEC 947-2 test
programwhichincludesradiatedandconductedemis-
sions testing. As a result, all units carry the CE mark.
2.0 DESCRIPTIONOF MAGNUM CIRCUIT BREAKERS
2.1 General
MagnumCircuitBreakers are tripped automatically on
overloadorfaultcurrentconditionsbythe combined
actionofthreecomponents:
1. TheSensors,whichmeasurethecurrentleveland
providetheenergytotrip
2. TheDigitripTripUnit,whichprovidesatrippingsignal
to the TripActuator when current and time delay
settingsareexceeded
3. Thelow-energyTripActuator, which actually trips the
circuitbreaker
Figure 2.1 shows this tripping circuit for a typical Magnum
CircuitBreaker.This arrangement provides averyflexible
system,coveringa wide range of trippingcharacteristics
describedbythetime-currentcurvesreferencedin
Section 9.2.
Theautomaticoverloadandshortcircuittrippingcharac-
teristics for a specific circuit breaker are determined by
the ratings of the installed current sensors with a match-
ingratingplug and the selected functional protection
settings.Specific setting instructions are provided in
Section 4.
When the functional protection settings are exceeded, the
Digitrip unit supplies a trip signal to the Trip Actuator. As a
result, all tripping operations initiated by the protection
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functionsofthe Digitrip Trip Unit areperformed by its
internal circuitry. There is no mechanical or direct mag-
neticaction between the primary current andthe mechani-
cal tripping parts of the circuit breaker, thus external
controlpowerisnotrequiredforoverloadorfault current
tripping.
WARNING
IMPROPERPOLARITY CONNECTIONS ON THE TRIP
ACTUATORCOILWILL DEFEAT THE OVERLOADAND
SHORTCIRCUIT PROTECTION, WHICH COULD RE-
SULT IN PERSONAL INJURY.
OBSERVEPOLARITY MARKINGS ON THE TRIP AC-
TUATORLEADSANDCONNECT THEMPROPERLY
USINGTHE INSTRUCTIONS PROVIDED.
2.2 Low-Energy Trip Actuator
Themechanicalforce required to initiate the tripping action
ofa Magnum Circuit Breaker is provided bya special low-
energyTripActuator.TheTripActuator is located underthe
black molded platform on which the Digitrip unit is sup-
ported.TheTripActuator containsapermanent magnet
assembly, moving and stationary core assemblies, a
Figure2.1 TrippingCircuitfor a Typical MagnumCircuit Breaker (Partial)
spring and a coil. Nominal coil resistance is 24 ohms and
the black lead is positive. The circuit breaker mechanism
assemblycontainsamechanism-actuated reset lever and
a trip lever to actuate the tripping action of the circuit
breaker.
When the TripActuator is reset by the operating mecha-
nism, the moving core assembly is held in readiness
againstthe force of the compressed spring by the perma-
nent magnet. When a tripping action is initiated, the low-
energyTripActuator coil receives a trippingpulse from the
Digitripunit.This pulse overcomes the holding effect ofthe
permanentmagnet,andthe moving core is released to
triggerthetrippingoperationviathe trip lever.
2.3 Ground Fault Protection
OnlytheDigitrip1150 cat# 11LSIG,11PLSIG and Digitrip
1150i cat. # 11IEC-EF,11PIECEF provide ground fault
protection.
2.3.1 General
WhentheDigitrip 1150familyincludes ground fault
protection features, the distribution system characteristics
(forexample,systemgrounding, number of sources,
number and location of ground points, and the like) must
beconsideredalong with the manner andlocationin which
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the circuit breaker is applied to the system. These ele-
ments are discussed in Sections 2.3.3 through 2.3.6.
TheDigitrip 1150 family uses three modes of sensing to
detectgroundfaultcurrents:residual, source ground, and
zerosequence(SeeTable 2.1).The breakersecondary
contact inputs B-6 and B-7 are used to configure the trip
unit.Ajumper from B-6 to B-7 programs the trip unit for
eitherasourcegroundorzerosequenceconfiguration.
Removingthejumperwillprogramtheunitfora residual
groundfault scheme. This jumper resides onthe stationary
side of the switchgear assembly. In all three schemes, the
propercurrentsensor input is required on the external
sensorinput terminals B-4, B-5of the breaker secondary
contacts.
Table 2.1 Digitrip Sensing Modes
2.3.2 Residual Sensing - 3-Wire or 4-Wire
ResidualSensingis the standard mode of ground fault
sensing in Magnum Circuit Breakers. This mode utilizes
onecurrentsensor on each phase conductorandone on
theneutralfor a 4-wire system (Shown inFigures 2.2
and 2.3).If the system neutral is grounded, and no phase
to neutral loads are used (a three wire system), the Digitrip
1150 with groundincludesall of the components neces-
saryforgroundfault protection. This mode of sensing
vectoriallysumsthe outputs of the three individual current
sensors.For separately-mounted neutrals, as long as the
vectorial sum is zero, then no ground fault exists. The
neutralsensor(for a four wire system) must havecharac-
teristics and a ratio which matches the three internally-
mountedphasecurrentsensors.Availabletypes of neutral
sensorsareshowninFigure 2.4.Residualground fault
sensingfeaturesareadaptable to main and feeder circuit
breakerapplications.
CAUTION
IFTHE SENSOR CONNECTIONSAREINCORRECT,A
NUISANCETRIPMAYOCCUR.ALWAYS OBSERVETHE
POLARITYMARKINGSON THE INSTALLATION DRAW-
INGS.TOINSURE CORRECT GROUND FAULT EQUIP-
MENTPERFORMANCE, CONDUCT FIELDTESTS TO
COMPLYWITH NEC REQUIREMENTSUNDERARTICLE
230-95(C).
2.3.3 Source Ground Sensing
Dependingupontheinstallation requirements, alternate
ground fault sensing schemes may be dictated (See
Figures2.6and 2.7). The ground returnmethod is usually
appliedwhenground fault protection is desired onlyonthe
main circuit breaker in a simple radial system. This
methodisalso applicable to double-ended systems where
amidpoint grounding electrode is employed. Forthis
mode of sensing, a single current sensor mounted on the
equipment-bondingjumperdirectlymeasuresthetotal
groundcurrentflowing in the grounding electrode
conductorandallother equipment-grounding conductors.
IntheCURRENT(protection) submenu, there is a setting
(EXTGNDCTRATIO) that enables the presentationof
groundpickupinamperes and the display of ground
currentinampereswhen an External Ground CT is
employed.This screen is presented when jumperB-6 to
B-7is present for a trip unitequipped with GROUND.
External Ground CT ratios of 10, 25, 50, 100, 200, 400,
800, 1000A:1 and “none” settings are selectable, with
“none”defaulting to the plug (In)rating. With the correct
ratio selected the GF pickup settings are adjustable in
amperes.
2.3.4 Zero Sequence Sensing
ZeroSequenceSensing,alsoreferredtoasvectorial
summation (See Figure 2.8), is applicable to mains,
feeders,andspecialschemesinvolvingzoneprotection.
ZeroSequencecurrenttransformers (4 1/2“ x 13 1/2“ [114
mm x 342 mm] rectangular inside dimensions) are
availablewith100:1 and 1000:1 ratios.TheEXTGNDCT
RATIO setting described above is applicable for zero
sequence.
2.3.5 Multiple Source/Multiple Ground
AMultiple Source/Multiple Groundscheme is shownin
Figure 2.9. In this figure, a ground fault is shown which
has two possible return paths, via the neutral, back to its
source.Thethreeneutral sensors are interconnected to
senseanddetect both ground fault andneutralcurrents.
2.3.6 Ground Fault Settings
Theadjustmentofthe ground fault functional settings and
theireffectuponthegroundfaulttime-currentcurveis
discussed in Section 4.2.1.8.
2.4 Current Sensors for Standard Breaker
Thethree(3-pole) or four (4-pole) primary current sensors
are located in the circuit breaker on the lower conductors
ofthebreaker.Thecurrentsensor rating defines the circuit
Ground
(Earth)
Fault Sensing
Method
Circuit Breaker
Secondary
Contacts Req’d
Applicable
Breakers
Figure
Reference
Digitrip GF
Sensing
Element Used
Residual No Jumper 3 or 4 pole 2.2, 2.3, 2.5, 2.9 element R5
Source Ground Jumper B6 toB7 3 pole only 2.7 element R4
Zero Sequence Jumper B6 to B7 3 pole only 2.8 element R4
Note: This information a
pp
lies to Tri
p
Units with Ground
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Page 13I.L. 70C1036H05
circuit breaker if the chip temperature is excessive. If the
unittripsonover-temperature,theredLongDelayTime
LED will flash and the OVER TEMP TRIP message will
appearonthe display.
TheDigitripusesthe Cutler-Hammer custom-designed
CHip™, an integrated circuit that includes a microcom-
puterto perform its numeric andlogic functions. The
principles of operation of the trip unit are shown in Fig. 3.1.
Allsensingandtripping power required to operate the
protectionfunctionisderivedfromthecurrentsensor
secondarycurrentswheneverthecircuit breaker is carrying
current.Thesecurrent signals develop analogvoltages
acrossthecurrentviewingresistors.The resulting analog
voltagesaredigitizedby the CHip™.
Themicrocomputer continually digitizes these signals.
This data is used to calculate true RMS current values,
whicharethen continually compared with the protection
functionsettings and other operating datastored in the
memory.Theembedded softwarethendetermineswhether
to initiate protection functions, including tripping the circuit
breakerthroughtheTripActuator.(TA)
3.2 Trip and Operation Indicators
The four cause of trip LEDs on the face of the trip unit,
shown in Figures 1.1 and 3.2 to 3.5, flash red to indicate
the reason for any automatic trip operation. Each LED is
strategically located in the related segment of the time-
currentcurve depicted on the faceof the trip unit. The
reason for the trip is identified by the segment of the time-
currentcurvewheretheLED is illuminated. Following an
automatic trip operation, the backup battery shown in
Figure 3.1 continues to supply power to the LEDs. The
LED pulse circuit, also shown in Figure 3.1, is provided to
reducebatteryburden and will flash the tripLED approxi-
matelyevery4 seconds. Therefore, it isimportantto view
the unit for at least 5 seconds to detect a flashing trip
indicator. Pushing the Reset button extinguishes the LED.
NOTE: Acompleteresetofthe Digitrip 1150requires the
unittobepowered(Status LED flashing) when depressing
theResetpushbutton.Otherwise,aprevioustripevent
may be indicated again by the LED.
3.2.1 Status/Long Pickup LED
The green Status LED will indicate the operational status
of the protection CHipAmicroprocessor of the trip unit.
Evenwithnoexternal power present, if the load current
throughthecircuitbreakerexceeds approximately 12 per-
cent(3 phase power) of the current sensorrating, the LED
will flash on and off once each second indicating that the
breakerrating(In).Forexample,2000A:1Asensorsare
usedona 2000Arated circuit breaker.Thereare also four
auxiliarycurrenttransformers with a ratio of10:1 which
furtherstepdownthe rated current to 100 milliamperes,
which is equivalent to 100% (In) in the Digitrip 1150.
Theprimarycurrentsensorsproduceanoutputpropor-
tionalto the load current andfurnish the Digitrip 1150
familywiththe information and energy required totrip the
circuitbreakerwhen functional protection settings are
exceeded.
WARNING
IF A SET OF CURRENT SENSORS WITH A DIFFERENT
RATIOARE INSTALLED IN THE FIELD, THE RATING
PLUGMUSTALSO BE CHANGED. THEASSOCIATED
RATING PLUGMUST MATCH THECURRENT SENSOR
RATING SPECIFIED ON THEPLUG LABEL. THE CUR-
RENTSENSOR RATING CAN BEVIEWED THROUGH
OPENINGSIN THE BACK OFTHE CIRCUIT BREAKER.
ALSOVERIFY DESIRED PROTECTION SETTINGS
AFTERTHESE COMPONENTSARECHANGED.
2.5 Current Sensors for Double Wide Circuit Breakers
Thesix(3-pole)or eight (4-pole) current sensors installed
in the circuit breaker are located on the lower conductors.
Thepolesareparalleled and the corresponding current
sensorsarealso paralleled (See Figure 2.3). forexample,
a4000Acircuit breaker phase rating has two2000:1
currentsensorswiredinparallel,which provides an overall
ratioof4000:2.Theauxiliarycurrenttransformershavea
ratio of 20:1 in this size circuit breaker to futher step down
the full load current to 100 mA.
3.0 PRINCIPLES OF OPERATION
3.1 General
TheDigitrip 1150 familyof trip units is designed for indus-
trialcircuitbreakerenvironmentswheretheambient
temperaturescan range from –20°C to+85°C,butrarely
exceed70°to75°C.If, however,ambienttemperatures
exceed this range, the trip unit performance may be
degraded.In order to insure that the tripping function isnot
compromisedduetoan over-temperature condition, the
Digitrip1150microcomputerchipshaveabuilt-inover-
temperatureprotection feature, factory set totrip the
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Effective 10/2004
Page 14 I.L. 70C1036H05
tripunitisenergizedand operating properly (See Figure
3.1).
Inanoverload (Long Pickup) condition thisstatus LED
flashes at approximately 4 times per second while the
overloadpersists.
3.2.2 Alarm LED
In addition to the green status LED, a yellow alarm LED is
providedto indicate real time alarmconditions existing on
thepowersystem.SeeAppendix D-16 for the programing
of these alarms.Also, if an unusual condition is detected
withinthe Digitrip’s hardwire or firmware,this LED will light
alongwithanALARM message.
3.2.3 Trip LED
The trip LED is illuminated upon any trip condition. It is
also a real time display and incorporates the circuit
breaker’s 52b auxiliary switch (also called MCR switch)
input for its logic. Pushing the Reset pushbutton or closing
the circuit breaker will clear this LED.
3.3 Making Current Release
AllDigitrip1150Trip Unitshave a Making Current Release
function.Thissafetyfeaturepreventsthe circuit breaker
frombeing closed and latched-in on a faultedcircuit. This
is a nonadjustable sensing circuit. It is preset to trip at an
instantaneouscurrentnumerically equivalent to 25 x (In).
(Note that currents of ~11 x (In) with maximum asymmetry
alsoreach this threshold.)
TheMakingCurrent Release is enabled only for thefirst
two cycles following an initial circuit breaker closing
operation.TheMaking Current Release will trip thecircuit
breakerinstantaneouslyandflashtheInstantaneousLED
as well as indicating “Making Current Trip” on the display
panel.
3.4 Zone Interlocking
CAUTION
IF ZONE INTERLOCKING IS NOT TO BE USED AND
ONLYSTANDARDTIME-DELAYCOORDINATIONIS
INTENDED,JUMPER TERMINAL B8 TO B9ON THE
CIRCUITBREAKERSECONDARYCONNECTOR.
ZoneSelectiveInterlocking (or Zone Interlocking) is
availableontheDigitrip1150 for the ShortDelayand
GroundFaultprotectionfunctions(SeeFigure 3.1).The
zone interlocking signal is wired via a single set of
wireslabeledZoneIn (Zin) and Zone Out (Zout)alongwitha
ZoneCommon wire. TheZoneSelectiveInterlocking
functioncombinesthe interlocking of Short Delayand
Ground Fault.Azone out signal is issued if the ground
fault pick-up is exceeded or if the short delay pickup is
exceeded or if the value of 2 x (Ir) is exceeded. Zone
SelectiveInterlockingprovidesthefastestpossibletripping
for faults within the zone of protection of the circuit breaker
andyetalsoprovidespositivecoordinationamongall
circuit breakers in the system (mains, ties, feeders, and
downstream circuit breakers) to limit a power outage to
only the affected parts of the system. When Zone Inter-
locking is employed, a fault within the zone of protection of
the circuit breaker will cause the Digitrip 1150 to:
•Tripthe affected circuit breaker immediatelyand, at the
same time,
•Issue a signal to upstream Digitrip units to restrain from
trippingimmediately. The restraining signal causesthe
upstreamcircuit breakers to follow their setcoordination
times, so that the service is only locally disrupted while
the fault is cleared in the shortest time possible.
Foranexampleofhow Zone Selective Interlocking may be
used, seeAppendixAof this Instructional Leaflet.
3.5 PT Module
ThePT(PotentialTransformer)Module(See Fig. 3.0 and
Appendix C) is internally wired in the circuit breaker to the
line side circuit breaker terminals. It provides signal data to
calculatevoltage,power,energyandrelateddata.The PT
moduleis a three phase, three wire inputand three wire
outputstepdowntransformerwithawyetowyehookup.
Thepower(andenergy)meteringandprotectioniscalcu-
latedwith the convention that power flow is from top to
bottom through the circuit breaker. This assumes the top
side conductor to be the line side. If the distribution
system is such that the bottom side is the hot side, the
powervalueswill indicate Reverse Power.Thisreadingcan
bemadean absolute value by installinga jumper from B-3
to B-7 of the secondary contacts.
CAUTION
ADIELECTRIC DISCONNECT PLUGLOCATEDON THE
LEFT SIDE OF THE CIRCUIT BREAKER IS PROVIDED
WITH THIS MODULE AND IS TO BE REMOVED WHEN
DIELECTRICTESTING OF THE CIRCUITBREAKER IS
CONDUCTED.FAILURE TO REMOVEPLUG WHEN
TESTING CAN RESULT IN DAMAGE TO TRIP UNITAND
PTMODULE.
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Figure2.2 3-Pole, 4-Wire Circuit Breaker with NeutralSensor Connections for Standard CircuitBreaker Using Residual
GFSensing
Figure2.3 Neutral Sensor Connections forDouble Wide Circuit Breaker Using Residual Ground Fault Sensing
In this scheme, all breaker secondary currents (at the 100mAlevel) are summed together at the
pc board donut transformer to sense ground fault via element R5.
No jumper on secondary contacts B-6, B-7.
Neutral input (if 4-wire) is via contacts B-4, B-5. Neutral current input to secondary contacts is 1A,
equivalent to 1 per unit ground.
Source
L
N
R
5
Digitrip
with GF
R/1
R/1
3
3
2
2
1
1
B-4
Load
Notes:
B-6
10:1
10:1 AUX. CT
B-5
B-7
Black
Trip
Actuator
+
-
L
B
L
C
L
A
1
1
1
Source
Load
B-4
B-6
20:1AUX. CTs
20:1
B-5
B-7
Black
Trip
Actuator
+
-
L
A2
L
B1
L
B2
L
C1
L
A1
L
N1
L
N2
L
C2
2000:1
2000:1
2000:1
2000:1
2000:1
2000:1
2000:1
2000:1
1
1
2
2
Notes:
R
5
Digitrip
with GF
In this scheme, all breaker secondary currents (at the 100mAlevel) are summed together at the PC
board donut transformer to sense ground fault via element .
In this scheme, the current sensors in the breaker poles are parallel-wired to achieve a 4000 amp
breaker rating. Other available ratings in this double-wide configuration are 6300A, 6000A, 5000A,
3200A, 2500A, and 2000A.
R5
3
Shown is ABCABC bus configuration.
3
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Figure2.4 DigitripNeutral Sensor Types
Figure2.54-Pole-3200AStandardCircuitBreakerUsingResidualGroundFault(Earth-Fault)Sensing
This will defeat all ground fault protection in application for 4 pole breaker.
5
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Figure 2.7 Source Ground Fault Sensing Scheme for Double Wide Circuit Breaker
Figure 2.6 Source Ground Fault Sensing Scheme for Standard Circuit Breaker
1150
:
1
2
3
4
1
2
3
4
Notes:
1 In this scheme, the current sensors in the circuit breaker poles are parallel-wired to achieve a 4000 Amp circuit breaker
rating. The ground fault is sensed directly via element R .
2 A on B-6, B-7 secondary contacts to program the Digitrip 1150 to use element R directly for source
ground sensing. If the circuit breaker is removed from the cell (B-6, B-7), jumper disconnected, Residual Ground setting
will apply.
3 Source ground sensor input is via B-4, B-5. Source ground current input to secondary contacts is 2A, equivalent to one
per unit ground. For example: Applying a 400:1 sensor - Use 800:2 ratio and use 800A value to calculate the ground pickup
setting.
4 The scheme is not applicable to 4-pole circuit breakers. No secondary contacts (B-4 & B-5) are available on 4-pole
circuit breakers. DO NOT jumper B-6, B-7 in 4-pole applications.
4
4
jumper is required
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Figure2.8 Zero Sequence Sensing Scheme for Standard Circuit Breaker
Figure2.9 MultipleSource/MultipleGroundScheme
If the breaker is removed
from cell (B-6,B-7) jumper disconnected, Residual Ground settings will apply.
1
2
3
4
R5R5
R5
φφ
T
M2
M1
B5 B4
I/2
G
I/2
G
I/2
G
I/2
G
I
G
I
G
i
g
i
g
i/2
g
i/2
G
i/2
g
i/2
g
i/2
g
Neutral Sensors Wired
in a Loop Configuration
B5
B5
B4
B4
NN
Internal
Digitrip
Sensor
Breaker M2 trips since this is the only breaker seeing the I fault via element R .
No jumper on B-6, B-7 terminals - all breakers are programmed for standard Residual Ground Fault
protection.
AUX CTs not shown. Wiring needed at system level is shown as a dotted line.
Capital letters represent primary current. Lowercase letters represent secondary current.
The three breakers (M1, M2, and T) must all have the same breaker/sensor rating.
G5
Notes:
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Page 19I.L. 70C1036H05
4.0 PROGRAMMING/VIEWING DIGITRIP 1150
(VIAFRONT PANEL)
4.1 Main Menu
4.1.1 Power Up Sequence
WhentheDigitrip 1150/1150iunitisfirst powered-up, two
differentdisplay messages are possible. If theDigitrip has
beenpreviouslycommissionedwith customer-made
settings,the display will alternate between “Customer
Settingsin Use” and “Eaton-Electrical DT1150”mes-
sages. Following this the display will enter into the main
menu(See Appendix D-1).
IfDigitripsettingshavenotbeensavedpreviouslythetrip
unit is using the factory default values. On power up, the
Digitripwillthendisplay“CHANGEFACTORYSETUP?”.
This message will stay on the screen until the user
presses ESCape or the SELect pushbutton or until an
alarm or trip condition is detected.
TheESCapepushbutton action will keep thefactory
settings and then will enter the main menu. The factory
settingsare listed inAppendix D-25and are not valid for
mostapplications.The appropriate settings need tobe
definedbyaqualifiedapplicationengineer to provide best
overallprotectionandcoordinationforthepowersystem.
A SELect pushbutton action will provide direct entry into
PROGRAMSETTINGmenu.Thefirstitempresentedis
theCurrentCURVE type. LSIG or IEEEor (IEC) current
curvetypes are possible selections depending ontrip unit
style. Pressing SELect again will select the curve pre-
sented in the window center and then step into the indi-
vidualelementsthatneedprogrammed.TheVIEWupand
downarrowselects the function while the EDIT upand
downarrow changes value.Afterthey are set theyneed to
besavedbydepressing the SAVEpushbutton.The saving
will place the customer settings in use. Verify the new
settings.SeeAppendixD-13forprogramcurveandD-19
forsavingandD-5 for view setting menu.
4.1.2 Pushbutton Definition
ViewFunctions
The“ViewFunctions” group of pushbuttons islocated in
the lower right hand side of the unit and includes the View
Up(uparrow),ViewDown(downarrow),ESCape,SELect,
andReset buttons.
ViewUp/ View Down - View UpandView Down allow the
usertoscroll through any available menu orsubmenu in
theDigitrip1150display.
SELect - The SELect pushbutton selects the submenu for
the blinking selection located in the middle of the display.
ESCape- The ESCape pushbutton brings theuser up to
theprevious menu in the display.Multiple ESC pushbutton
operationwilldisplay Main Menu screen.
Reset - The Reset pushbutton will reset LEDs and screen
data(SeeResetSequence).
Edit Values
The“EditValues”grouplocatedin the upper left hand
corner of the Digitrip 1150 unit consists of 3 pushbuttons:
EditUp(indicatedby an up arrow), Edit Down (downarrow)
andSave.The Edit Values pushbuttons arecoveredby a
Plexiglass cover which can be sealed.
Edit Up / Edit Down - Edit Up and Edit Down allow the user
toscrollupor down, respectively,through available setting
values while in any Program Settings submenu. In the Test
Menu, these buttons will raise or lower the test level when
performingaself test.
Save- The Save pushbutton allows theuserto save a
groupofselectedprogrammablesettingsfromany
submenu in the PGM SET menu. Save is also used in the
Figure 3.0 PT Module with Dielectric Disconnect Plug
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Figure 3.1 Digitrip 1150 Block Diagram with Circuit Breaker Interface
(Load/Lower)
(Line/Upper)
NABC
AUX CTs
Residual
Ground
Detection
Typical Phase or Ground Sensing Resistor
Bridge
Circuits Internal
Power
Supply
PT Module
Making Current
Release Circuitry
(See Section 3.3)
Trip Actuator
LED
Pulse
Circuit
+3V Battery
POWER/RELAY
Module
FET
Trip Trip LEDs
CHip
TM
CHip Chip
TM
TA
Current Sensors
4 bit Latch Chip
Zone Interlocks Z
IN
Z
OUT
Rating
Plug
Key
Pad
A
B
INCOM
Trans-
ceiver
Accessory
Bus
Aux Relay
Drivers
Chip
CURRENT Protection
Display &
VOLTAGE
PROTECTION
Alarm
Trip
Status LED
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