weschler instruments OMBGP100 User manual

ACP4 BarGraph Watt & Var Meters
Owners Manual
Manual Part Number OMBGP100
Revision 1, June, 2006
16900 FOLTZ PARKWAY, CLEVELAND, OHIO 44149
440/238-2550, FAX [phone] e-mail: [email protected]

Table of Contents
Title Section Page
Introduction .................................... 1.0..................................... 1
Description
Intended Usage
Models and Features
ReceiptInspection .............................. 2.0..................................... 4
Installation .................................... 3.0..................................... 4
Connections, Power Requirements & Fuse Ratings
Mounting and Terminal Assignments
Configuration .................................. 4.0..................................... 9
Keystroke-by-keystroke Set Up Guide
Supervisory Setup, Keystroke Diagrams
Operation ..................................... 5.0.....................................14
Calibration .................................... 6.0.....................................16
Troubleshooting ................................ 7.0.....................................18
Specifications .................................. 8.0.....................................21
Warranty...................................... 9.0.....................................23
Figures
1. Display and Controls ................................................................ 2
2.TerminalAssignments ............................................................... 3
3. Base Terminal and Fuse Location (standard base) ......................................... 3
4. Interfacing a PC for RS-485 Communications with Multiple BarGraphs ......................... 6
5. Signal Connections (5A - 5J) ......................................................... 7-8
6.JumperLocations................................................................... 9
7. Supervisor Mode Configuration Keystroke Diagram (7A & 7B) ................................13
8. Operator Mode Keystroke Diagram .....................................................15
9. Single Phase Test Connections ........................................................16
10. Outline, Cutout and Drilling (3A - 3C) ..................................................22
Tables
1.FeatureComparisonSummary ........................................................ 2
2.RelayContactRatings............................................................... 5
3. Fuse Ratings (3A Standard, 3B Enhanced, 3C TriColor) ....................................18
4. Connection Error Symptoms (4A- 3P 3W; 4B- 3P 4W) ......................................19
5Specifications ......................................................................21

1.0 Introduction
Description
The ACP4 BarGraph watt and var meters are part of the ACP4 series of AC power instruments, comprising voltmeter,
ammeter, watt meter, var meter and power factor functions. The instruments in the series are driven by the latest state of
the art technology, utilizing a digital signal processing (DSP) IC for power measurement and conversion and a
microprocessor for function coordination, configuration, communications and display presentation.
Intended Usage
TheACP4seriesinstruments are intended forusewhereverthere exists a needformeasurementsofACpowerquantities
of high accuracy and reliability in an industrial quality switchboard instrument. Some models are available in military
ruggedized and spray-tight versions; consult the factory for availability of these models.
In existing applications, the Weschler ACP4 series watt and varmeters are intended to replace analog instruments such
as the Weschler or Westinghouse KP-241 and KP-261, KV-241 and KV-261 and the GE / Yokogawa AB40. In new
applications the ACP4 series is ideally suited where an increased level of functionality is desired.
Models and Features
The watt and var models are identified by the three character prefix BGP ( watt meter), BGG ( var meter for use with a
phase shifting transformer) or BGV (var meter for use without a phase shifting transformer). The ACP4 series is available
in standard switchboard sizes identified by the three digit suffix 241 ( 4 ½ inch square ), 251 ( 7 ½ inch round ) 261( 8
¾ inch square) and 281 ( 10 inch round ). All sizes are available in the standard and enhanced display configurations.
TriColor versions are available in 241, 261 and 281 sizes. Standard, Enhanced and TriColor models are primarily
differentiated by their display presentation, although the feature set becomes more flexible from standard to TriColor
models.
The standard BarGraph is available with a red, green or amber numeric display with a measurement range of -19999 to
+19999 counts. The standard bar color is red. Fixed position color zones are possible in the bar display, but brightness
ofthe green andamber colors maybea problem inareas wherehigh ambient lightintensity exists. Itisrecommended that
if color zones are required in the bar, that the enhanced or TriColor models be considered.
The Enhanced model is available with red, green or amber color numeric displays with a measurement range of -9999 to
+50000 counts. The standard red bar color is a very bright, sunlight readable intensity. The bar display can be a solid red,
green or amber, or mixed, fixed-position color zones. The amber and green colors are suitable for high ambient lighting
intensity, but may not be suitable for sunlight readability. The enhanced models also has a dual-level display brightness
setting that is programmable from the front panel buttons.
The TriColor model is available with a red, green oramber numeric display witha measurement range of ± 50000 counts.
Thebar display canbe programmed for zoned orbanded patterns,with contrasting set pointsthat delineate theboundary
ofthebandsorzones.Byprogrammingthefoursetpointvalues,thebarmaybesettochangecolorsatdifferentmeasured
signalmagnitudes, insuringthatoperators areinstantlyaware ofoperationwithin oroutsideof normal boundaries,without
reading the actual value.
OMBGP100 Rev 1 Page 1 of 23

Figure 1. Standard ACP4 BarGraph Dial and
Front Panel Features
Figure 2. Enhanced and TriColor ACP4
BarGraph Dial and Front Panel Features
Enter / Save Button
Decrement Button
Increment Button
Table 1. Feature Comparison Summary
Feature BGP Wattmeters, BGG and BGV Varmeters
Standard Enhanced TriColor
Measurement Range ± 19999 -9999 to 50000
(Neg Autoscale) ± 50000
Basic Accuracy ± 0.5% FS, ± 1 Count ± 0.5% FS, ± 1 Count ± 0.5% FS, ± 1 Count
Potential Range 120, 240 vrms 120, 240 vrms 120, 240 vrms
Self-Contained Current Maximum 10.00 arms 10.00 arms 10.00 arms
Numeric Display Characters 4 ½ Digit 4 ¾ Digit 4 ¾ Digit
Numeric Display Colors Red, Green, Amber Red, Green, Amber Red, Green, Amber
Bar Colors Red, Green, Amber (note 1) Red, Green, Amber Red, Green, Amber
Bar Color Arrangement Fixed Zones Fixed Zone Programmable Zone or Band
Display Brightness Fixed Two Level Programmable 16 Level Programmable
Alarm Hysteresis 0.5, 1 & 2 % FS for All Alarms 0.0-10.0% FS for All Alarms 0.00-10.00 % FS for All Alarms
Relays 2 OR 4 Form C 2 OR 4 Form C 2 OR 4 Form C
Relay Latching N/A Yes Yes
HI - LO Alarms 2 HI, 2 LO Individually Programmable Individually Programmable
Analog Retransmit 256 Step Resolution 65000 Step Resolution 65000 Step Resolution
Communications RS-232 or 485 RS-232 or 485 RS-232 or 485
Decreasing Trend Annunciator 51 Segment Bar Display
Increasing Trend Annunciator
Alarm 3 Lo Annunciator Alarm 2 Hi Annunciator
Alarm 4 LoLo Annunciator Alarm 1 HiHi Annunciator
4 ½ Digit Numeric Display
OMBGP100 Rev 1 Page 2 of 23

Decreasing Trend Annunciator
Alarm 3 Annunciator
Alarm 4 Annunciator
Enter/ Save Button Increment button
Decrement Button
Wickman type 374/TR5 Time Lag Fuse.
Note relationship of pins to the line marked
on the fuse body.
Communications Wiring
Terminal RS-232 RS-485
1TX-
2 COM GND
3RX+
Figure 3. Base Terminal and Fuse Location
(standard base)
Increasing Trend Annunciator
Alarm 2 Annunciator
Alarm 1 Annunciator
4 ¾ Digit Numeric Display
Relay, Retransmit and Communications
Connectors are Phoenix-Type. Plugs are
Furnished if These Options are Ordered.
#6-32 Screw Terminals
OMBGP100 Rev 1 Page 3 of 23

2.0 Receipt Inspection
Packaging Inspection
The packaging in which your BarGraph is shipped is designed to protect its contents against normal shipping shock and
vibration. If the external carton is damaged in any way, report any damage to the carrier as soon as possible and
immediately unpack the carton for internal inspection.
Unpacking
The BarGraph is packaged with this manual, a software manual if equipped with digital communications, a mounting
hardware kit, Phoenix-type plugs for mating with installed option connectors and a spare fuse. Other accessories such as
calibration tools, or other items which may have been ordered at the same time will be included only if the packaging
integrity is not compromised. Please remove all packing materials and check them for included accessories before
discarding them.
Physically inspect the BarGraph and its accessories for signs of hidden shipping damage. Evidence of excessive
roughnessinshippingincludeadentedcaseandcrackeddisplaywindows.Shaketheinstrumentandlistenforanyrattling
which would indicate parts adrift inside the case.
3.0 Installation
All signal and power connections are made to the terminal strips (standard base) or terminal studs (molded base). The
molded base is primarily supplied for compatibility with Weschler and Westinghouse analog instruments. The number of
terminalstudsavailableinthemoldedbasearelimitedbyspaceconstraints,andterminalassignmentsarethereforemade
depending upon the options ordered. See figure 6A - 6Z for option connections when the molded base is supplied.
On the Standard base, alarm relay, analog re-transmit and communications connections are made through Phoenix style
receptacles and plugs rated for 300v, 8 amp service. The plugs are provided in the installation kit for the receptacle
correspondingtoanordered option. Additionalorreplacement plugsare available fromWeschlerorelectroniccomponent
supply companies according to the following table:
Receptacle Weschler Part Number Manufacturer Mfg Part Number
Retransmit 2100003602 Phoenix 1803426
Relay 2100003612 “ 1803439
Communications 2100003603 “ 1803523
Analog Retransmit Connections
The analog retransmit output is available in two forms; PWM and DAC. The PWM style, supplied only on the standard
ACP4 BarGraph, is a constant voltage type with 256 step resolution. It is available in isolated and non-isolated versions.
Because the voltage is proportional to the signal, the loop resistance, including the load and lead resistance, must be
carefully calculated in order to maintain the accuracy of the output current. If the loop resistance varies from the specified
value,theoutputcurrentwillhaveaproportionalerror.Normallywhenusingthistypeofoutput,theloopresistanceisbelow
the value specified and it is padded up to the required value with an external resistor.
The DAC retransmit is supplied on the Enhanced and TriColor ACP4 BarGraphs. It is a constant current type with 65000
step resolution. It is available in isolated output only. The constant current output means that the output will be unaffected
by loop resistance within the loop resistance limits of 0 to 1000 ohms. This type of retransmit is configurable through front
panel programming buttons for any current between 0 and 24 ma corresponding to any on-scale signal span. The output
is not bipolar, however; if can only produce positive current values.
On both output types, 20 to 24 AWG, 300 volt, 105 EC hook up wire is recommended.
OMBGP100 Rev 1 Page 4 of 23

Alarm Relay Connections
The alarm relay contacts are rated for 5 amps maximum, and the hook-up wire should be selected accordingly. The
potential rating of the relay contacts is related to the current rating as shown in table 2.
Table 2. Relay Contact Ratings
Contact Current Rating ...........@ ........... PotentialRating Load
NO 5A.................................. 30vdc Resistive
5A............................... 120 / 240 vac “
1/14HP.............................. 120/240 vac Inductive
NC 5A.................................. 30vdc Resistive
5A............................... 120 / 240 vac “
1/10HP............................. 120 / 240 vac Inductive
It is recommended that insulation be selected with a minimum 600 v, 105 EC rating.
Signal and Power Connections
Theterminalstripsused in ACP4 BarGraphareratedfor20 amps,250volts rms. Theterminalscrewsshouldbe tightened
to 8 - 11 inch pounds. The maximum torque on the screws, without thread damage, is 13 inch pounds. Lead terminating
lugs must be suitable for #6-32 terminal screws with a maximum lug width of 5/16 (0.312) inches. Actual connection
diagrams are presented in figure 5 below.
Current Circuits
CAUTION! CAUTION!
Special attention must be taken when wiring to the current sense circuit if it is connected directly to a current
transformer (CT), since the open secondary of a CT can generate high voltages which are lethal to personnel.
Precautions must be taken to either de-energize the current circuit (preferred) or short circuit the CT secondary before
making any wiring changes. Consult with your safety personnel for appropriate practice prior to making any current circuit
connections.
The BarGraph’s current circuits have ratings up to 10 amps maximum continuous, though the actual rating of your
BarGraph may be less. The BarGraph current circuits are designed to withstand the 1000% momentary current overload
and 120% sustained current overload specified in ANSI C39.1-1981, and the terminal lugs and hook-up leads must be
capable of carrying this current as well, if the C39.1 overload is required. It is recommended that the wire have a 600 volt,
105 EC insulation rating. Consult national and local wiring standards for actual wiring requirements.
Potential Circuits
The BarGraph potential circuits are ultra low burden circuits which draw less than 1 ma of compliance current. Although
this current is very low, it is recommended that the external wiring be 20 AWG or greater diameter with a 600 volt, 105 EC
insulation rating. Consult national and local wiring standards for actual wiring requirements.
Power Circuit
The BarGraph can be powered from the power sources listed in table 2. The maximum compliance current (825 ma) of
all BarGraph ACP4 instruments is drawn by the TriColor instrument at the 12 vdc source voltage level with maximum
brightness, full amber bar and all relays picked up. All other instruments in the BarGraph ACP4 series draw less current.
Itisrecommendedthattheexternalwiringbe20AWGorgreaterdiameterwitha600volt,105ECinsulationrating.Consult
national and local wiring standards for actual wiring requirements.
OMBGP100 Rev 1 Page 5 of 23

COMPUTER
COMMPORT
DB-9CONNECTOR
RS-232 TO RS-485
CONVERTER
TX
RC
RTS
GND
2
3
4
7
2
3
7
5
TX-
TX+
RC-
RC+
GND
BarGraph
WITH UNIT
ID SET TO
00
1(-)
2
3(+)
COMM PORT
BarGraph
WITH UNIT
ID SET TO
01
1(-)
2
3(+)
COMM PORT
BarGraph
WITH UNIT
ID SET TO
99
1(-)
2
3(+)
COMMPORT
UNIT IDS CAN
RANGE FROM
00 TO 99
R1
R1
R1
R1
R2
R2
2
5
14
17
7
DB-25 CONNECTORS
EXTERNAL
POWER
SUPPLY
Figure 4. Interfacing a PC for Digital Communications with Multiple BarGraphs
Digital Communications Connections
The ACP4 series BarGraphs support full duplex RS-232 and half-duplex (2-wire), multidrop RS-485 communications.
For RS-232 applications, BarGraph comm connector terminal 1 (transmit) is connected to the host’s receive terminal and
BarGraph comm connector terminal 3 (receive) is connected to the host’s transmit terminal. The BarGraph comm
connector terminal2 (common)is connectedto thehost’s commonterminal.The commonterminalis notanearth ground
connection. It is intended as a signal reference between the BarGraph and the host only.
For RS-485 applications, BarGraph comm terminal 1 (-) is connected to the host’s (-) terminal and BarGraph comm
terminal 3 (+) is connected to the host’s (+) terminal. The BarGraph comm connector terminal 2 (common) may or may
not be necessary for system operation. It is normally used to suppress common mode voltage on the two active lines.
When it is required to be connected, it is recommended to add a 100 ohm resistor in series with the host in order to limit
surgecurrents.TheRS-485standardallows32devicestobeconnectedtothesamepairoflines.Inmultidropinstallations
it may be necessary to connect a 125 ohm resistor across the terminals of the last device in the string in order to suppress
signal reflection. It is recommended that the system be operated without the resistor and ad it only if the system operates
unsatisfactorily.
A common communications circuit which is used to interface a PC to BarGraph and other RS-485 devices, employs an
RS-232 to RS-485 converter, as illustrated in Figure 4. In this diagram, the user is communicating with three BarGraphs,
each with its own unique comm identification number.
Notes for Figure 4
1. The computer, converter, cabling and resistors shown are user supplied.
2. Add 100 ohm resistors (R1) between the signal ground of the converter and terminal 2 of each BarGraph.
3. Add120ohmresistors(R2)attheoutputoftheconverterandacrosstheterminalsofthelast BarGraphonthebranch.
4. Upto32BarGraphsmaybeconnectedtoacommonRS-485branchcircuit.EachBarGraphmusthaveitsownunique
unitID,selectedfromarangeof00to99 hex (153 decimal). Note thattheBarGraphdisplayshowsunitID'sasdecimal
numbers, but the actual protocol uses hex numbers. The decimal number shown on the display must therefore be
converted to hex in order for the host to correctly address the BarGraph.
OMBGP100 Rev 1 Page 6 of 23

Figure 5D. 1 Phase 2 Wire Type
BGP Wattmeter and BGV
Varmeter with Molded Base
Connection Diagrams
Thediagramsbelowpresent all common powermeasurementschemes. The alarmrelay,communicationsandretransmit
connections are omitted, since these are well known circuits or have been described above.
Figure 5C. 3 Phase 4 Wire Type
BGP Wattmeter & BGV Varmeter
Figure 5B. 3 Phase 3 Wire Type
BGP Wattmeter & BGV Varmeter
Figure 5E. 3 Phase 3 Wire Type
BGP Wattmeter and BGV
Varmeter with Molded Base
Figure 5A. 1 Phase 2 Wire Type
BGP Wattmeter & BGV Varmeter
Figure 5F. 3 Phase 4 Wire Type
BGP Wattmeter and BGV Varmeter
with Molded Base
OMBGP100 Rev 1 Page 7 of 23

Figure 5I. 3 Phase 4 Wire, 3 PT
Type BGV Varmeter
Figure 5G. 3 Phase 4 Wire Type BGG
Varmeter for Use with Phase Shifting
Transformer
Figure 5H. 3 Phase 4 Wire Type BGG
Varmeter with Molded Base for Use with
Phase Shifting Transformer
The following connections are less common, but are supported by APP-4 BarGraphs:
Figure 5J. 3 Phase 4 Wire, 3 PT
Types BGP & BGV Wattmeter &
Varmeter with Molded Base
OMBGP100 Rev 1 Page 8 of 23

BGG/BGP/BGV 251 & 281
BGG/BGP/BGV-241
BGG/BGP/BGV 261
Jumper Block JA2
Figure 6. Jumper Locations
Jumper JA1
Jumper JA1
Position Unused
Numeric Display Flash Inhibit (stops flashing of numeric display only)
Numeric and Bar Display Flash Inhibit
Lamp Test
OMBGP100 Rev 1 Page 9 of 23

4.0 Configuration
Supervisor Mode
The supervisor mode is provided to allow users to configure all user programmable settings. These settings should be
changed only by knowledgeable individuals, since the calibration and / or operation of the BarGraph can be seriously
affected by the values entered in this mode.
In order to enter the supervisor mode, thecover and dial ofthe instrument must be removed and a jumper must be placed
across the pins of jumper header JA1. Refer to figure 6 for locations of the jumpers on your BarGraph. When supervisor
setup is first entered, the prompt “CnF” will appear in the numeric display.
The keystrokes of figures 7A and 7B Are used to configure a standard ACP4 BarGraph.
Keystroke by Keystroke Guide to Configuration
This guide explains what the keystrokes in the supervisory set up loop are for and how they impact ACP4 BarGraph
function. The bold paragraph heading indicates a main loop prompt. Normal font paragraph headings indicate sub-loops
where the actual parametric values are entered.
In order to enter the main loop, the cover and dial must be removed from the instrument and a jumper placed across the
JA1 header. See figure 6 for the location of the jumper header in your BarGraph model. The jumper is a standardtype for
use with pin headers of 0.1 inch spacing and 0.025 inch square pins.
CnF
This prompt indicates the entry and end points for the supervisor mode ConFiguration loop. It has no other significance
other than to let the user know that the entire loop has been traversed. It is not necessary to scroll to this prompt in order
to exit the loop. The loop will be exited as soon as the jumper is removed from JA1.
PEA
ThePEAk isa togglewhich functionallows the userto turn thepeak / valleyfunction on or off. Thepeak andvalley feature
continuously monitors the measured quantity (watts or vars) and records the highest and lowest value. The valley value
maybedisplayedbypressingthedecrementbuttonatanytimeduringnormaloperation.Thepeakvaluemaybedisplayed
by pressing the increment button at any time during normal operation. To reset the peak value, press the enter and
increment buttons simultaneously. To reset the valley value, press the enter and decrement buttons simultaneously. The
peak and valley values are stored in volatile memory, meaning that if instrument power is lost, the peak and valley values
will be lost.
After choosing an option value, be sure to press the enter button to save the choice.
HYS
The hysteresis value specifies the magnitude of the dead band between the alarm set point and the alarm drop out point,
for all alarms. The value is expressed as a percent of scale.
When referred to set point operation, hysteresis is the magnitude, or amount, that a process value must retreat from an
alarm condition, to cause the alarm to reset. After choosing an option value, be sure to press the enter button to save the
choice.
OMBGP100 Rev 1 Page 10 of 23

ZErO
This function is a calibration operation, which sets the signal value that is to be applied and the number to be shown on
the numeric display at ZErO scale. See the calibration section for details on how to use this function. If you are not totally
prepared to calibrate the instrument, do not enter this function. If this loop is incorrectly executed, the calibration of the
instrument can be grossly affected.
FULL
This function is a calibration operation, which sets the signal value that is to be applied and the number to be shown on
the numeric display at FULL scale. See the calibration section for details on how to use this function. If you are not totally
prepared to calibrate the instrument, do not enter this function. If this loop is incorrectly executed, the calibration of the
instrument can be grossly affected.
bAr
The bar function sets the origin of the bar display. The origin is the point from which the bar display “grows”. The bar
function is NOT a calibration function and it only affects the bar display. There are five absolute values and three relative
positions. After choosing an option value, be sure to press the enter button to save the choice.
Absolute values
The absolute value options represent a percentage of full scale span from the left end scale. The “0” value ( 0%) sets the
origin to the first LED at the left end scale. The “25", “33", “50" or “100" values set the origin at 25%, 33%, 50% or 100%
of full scale. When an absolute value of 25, 33, or 50 is chosen for the bAr variable, and a negative signal polarity is
applied, the bar display will grow from the origin to the left end scale. When an absolute value of 25, 33 or 50 is chosen
for the bAr variable, and a positive signal polarity is applied, the bar display will grow from the origin to the right end scale.
If “100" is chosen the bar will grow from the right end scale towards the left end scale with application of a positive signal
polarity. The bar will not respond to a negative signal polarity.
bIP
The bIPolar option moves the origin point from left to right end scale automatically, depending upon the polarity of the
signal. The origin is placed at 0% of full scale and the bar grows towards the right end scale as the signal magnitude
increases in the positive polarity. The origin is placed at 100% of full scale and the bar grows towards the left end scale
as the signal magnitude increases in the negative signal polarity.
vAr
The vAriable option allows the user to explicitly specify values for the origin and right bar end scale, based on absolute
signal (numeric display) values. The origin is always placed at the first LED at the left end scale. This function is used with
the bZr (set bar zero scale) and bFL (set bar full scale)to set the origin and right end scale values respectively.
This feature is used to expand the bar display within a signal range of particular interest, to indicate at a distance that a
process is within limits.
dEv
The dEviation option allows the user to explicitly specify values for the left and right bar end scales, based on absolute
signal (numeric display) values. The origin is always placed at the center LED of the bar. The signal value associated with
theoriginiscalculatedbytheBarGraphtobethemedianpointbetweentheleftandrightendscalevalue.Thebarwillgrow
fromthe origintoward leftend scaleforany signal valuelessthan themedianpoint value. The bar will grow from the origin
toward right end scale for any signal value greater than the median point value. This function is used with the bZr (set bar
zero scale) and bFL (set bar full scale) functions. The bZr function is used to specify the left end scale in absolute signal
value and the bFL function is used to specify the right end scale in absolute signal value.
OMBGP100 Rev 1 Page 11 of 23

OPr
TheOPeratorisa toggle function whicheitherenablesordisables theoperatormodefeature.The option has twochoices;
“On” (enable) or “OFF” ( disable). See the Operator Mode section above for capabilities provided with this feature. After
choosing an option value, be sure to press the enter button to save the choice.
dEC
The dECimal function allows the user to scale the numeric display to any decade value by moving the radix to any of five
positions. Pressing the increment or decrement buttons moves the radix left or right to the actual position it will occupy
during normal operation. Reference the dEC keystrokes of figure 7B.
bZr
This prompt will only appear if the dEv (deviation) or vAr (variable) option is chosen in the bAr loop. The values set by this
function are different when used in conjunction with either the deviation or variable option. Please refer to the dEv or vAr
function, above for more details.
bFL
This prompt will only appear if the dEv (deviation) or vAr (variable) option is chosen in the bAr loop. The values set by this
function are different when used in conjunction with either the deviation or variable option. Please refer to the dEv or vAr
function, above for more details.
Id
The communications Identification number function is used to set the digital communications address which is used by
a host computer to uniquely identify a single intelligent electronic device (IED) on a communications cable with multiple
connected IED’s. The ID number can be of any value between 0 (default) and 255.
OMBGP100 Rev 1 Page 12 of 23

Figure 7A. Supervisor Set Up Loop
ENT
0000.0
ENT
CnF
ENT
AL1
RUN
ENT
HI
Lo
ENT
LCH
rEL
ENT
+/- ES
0000.0
NUMERIC DISPLAY
ENTER
BUTTON INCREMENT
BUTTON
DECREMENT
BUTTON
ENT
AL2
ENT
HI
Lo
ENT
LCH
rEL
ENT
+/- ES
0000.0
ENT
AL3
ENT
HI
Lo
ENT
LCH
rEL
ENT
+/- ES
0000.0
ENT
AL4
ENT
HI
Lo
ENT
LCH
rEL
ENT
+/- ES
0000.0
ENT
PEA
ENT
on
OFF
ENT
HYS
ENT
LCH
00.0
ENT
ZErO
ENT
0000.0
0000.0
ENT
FULL
ENT
0000.0
0000.0
ENT
bAr
ENT
0
25
33
50
100
bIP
vAr
dEv
FROM
Id TO
OPr
All alarms are configured identically. If the hardware
which supports the alarm is not installed,the submenu
for that alarm will not appear.
The PEA (peak) on / off toggle turns this function on or off.
The HYS function provides for setting a hysteresis value for all alarms.
This is a calibration function. Do not disturb settings unless you are fully
prepared to perform a full calibration. See the calibration section 6 for details.
This is a calibration function. Do not disturb settings unless you are fully
prepared to perform a full calibration. See the calibration section 6 for details.
Thisfunctionprovidesa means of settingupthebardisplay’sresponsetosignal
inputs.
OMBGP100 Rev 1 Page 13 of 23

Figure 7B Supervisor Set Up Loop (conclusion)
TO
OPr
ENT
dEC
ENT
xxx0x
xxx1x.
xxx2.x
xxx.3x
xx.x4x
x.xx5x
ENT
OPr
ENT
OFF
on
ENT
b2r
ENT
0000.0
0000.0
ENT
bFL
ENT
0000.0
0000.0
ENT
Id
ENT
255
0
FROM
bAr
This function enables (on) or disables (OFF) the operator mode.
This function allows for positioning of the radix (decimal point).
` This non-calibration function works in conjunction with the bAr function
toallowspecificationofbardisplayendscalepointsintermsofabsolute
signal values.
` This non-calibration function works in conjunction with the bAr function
toallowspecificationofbardisplayendscalepointsintermsofabsolute
signal values.
This function specifies the communications address of the instrument.
5.0 Operation
The ACP4 series watt and varmeters are designed to provide many years of low maintenance, trouble free service. The
recommended calibration check interval is five years and in the unlikely event that re-calibration is required, it is a simple
process requiring only a watt standard, a few keystrokes and whatever time the standard requires for warmup.
There are no components to adjust or select. All adjustments are made from the front panel. Calibration can be
accomplished in the panel or on the bench. Please refer to section 6 for calibration procedure.
The only other maintenance that may be required is cleaning of the dial window. This should be done with a soft cloth
moistened with a mild liquid dishwashing detergent such as Dawn, mixed one table spoon of detergent to one quart of
water. Wipe the window area with another cloth dampened with clear water to rinse off any remaining detergent. Avoid
getting water into the button holes of the BarGraph.
OMBGP100 Rev 1 Page 14 of 23

ENT
0000.0
Press and hold the ENTER button for three seconds.
ENT
CnF
After three seconds "CnF" will appear in the numeric display if operator mode
has been enabled. See supervisor setup for instructions on enabling the
operator mode.
ENT
CnF
ENT
AL1
RUN
Pressing the ENTer button while the "CnF" prompt
appears in the display will cause execution to branch
back to normal operation.
ENT
HI
Lo
ENT
LCH
rEL
ENT
+/- ES
0000.0
ENT
AL2
ENT
HI
Lo
ENT
LCH
rEL
ENT
+/- ES
0000.0
ENT
AL3
ENT
HI
Lo
ENT
LCH
rEL
ENT
+/- ES
0000.0
ENT
AL4
ENT
HI
Lo
ENT
LCH
rEL
ENT
+/- ES
0000.0
Once the operator mode has been entered, the alarms can be configured using the keystrokes below. The menu
structure can be navigated without changing any values as long as the increment or decrement buttons are not
pressed. If it is desired to save a value, the enter button must be pressed after scrolling to the new value with the
increment and / or decrement buttons.The alarm sub menues will only appear if the hardware that supports it is
installed. If no alarm hardware is installed and the operator mode is entered, only the"CnF" pompt will appear.
INCREMENT BUTTON
DECREMENT BUTTON
ENTER BUTTON
NUMERIC DISPLAY
If no button activity has been logged for 45 seconds, the BarGraph willl revert to normal operation. While in
operator mode, all background processes, including alarm operation, communications and analog retransmit
continue to function normally. Changes to alarm values will take effect after resuming normal operation.
Setting Can Be Viewed, but
not Changed in Operator Mode
Figure 8. Operator Mode Keystroke Diagram
Operator Mode
Theoperator modeprovides forlimited accesstoBarGraph alarm function.The Hi (ascendingtrip) or Lo(descending trip)
settings may be viewed and the set point value may be changed. In addition, if the alarm has been set to latching type,
the relay’s state-of-alarm (latched or released) can be viewed and if latched, may be released.
Theoperatormodecanonly be entered ifithasbeenenabledinthesupervisorsetuploop.Seethenexttopic,“Supervisor
Mode” for keystrokes necessary to enable the operator mode
OMBGP100 Rev 1 Page 15 of 23

Figure 9. Single Phase Test Connections
6. Calibration
ACP4 calibration is performed by comparison of the BarGraph indication the indication of standards of higher accuracy.
To set up for calibration you will need the following equipment:
1 A watt / var calibrator capable of sourcing appropriate currentand potential levels and shifting the phase angle of the
current with respect to the potential by ± 90E.
2. If a watt / var calibrator is not available, an individual current and potential source that is capable of sourcing current
and potential corresponding to the values that are applied in the application, plus a watt / var standard (Voltech
PM3000ACE or equivalent), plus a phase shifter capable of shifting the phase angle of the current with respect to the
potential by ± 90E.
Calibration Procedure
1. Connect the BarGraph potential circuits in parallel and the current circuits in series as shown in figure 9. Polarity is
indicated by the “ ± “ character.
OMBGP100 Rev 1 Page 16 of 23

Calibration Procedure (continued)
2. Remove the cover and dial from the BarGraph. Place a jumper on pin header JA1.
3. Turn on and warm up the BarGraph and the test equipment. BarGraph warm-up time is negligible.
4. Recordthesingle phase testwatts fromthedataplate attachedtothe sideofthe BarGraph. Ifthe data plateis illegible
or missing, calculate the value from one of the following equations:
Single Phase: SPTW = Scale
PT x CT
3 PH 3W: SPTW = Scale
PT x CT x 2
3PH 4W SPTW = Scale
PT x CT x 4
These equations are correct for most common connections; however, there are instances where unique connection
schemes have been developed to accommodate unique systems. In the event that you are connecting the BarGraph
to a system with a connection scheme that does not appear in this manual, contact the factory for instructions.
If the BarGraph being calibrated is a self-contained var meter, type BGV, skip down to step 10.
5. Energize the test circuit and adjust the potential to the BarGraph’s rated voltage.Adjust the current output to zero and
shunt the current input to the test circuit. The standard should be indicating zero watts.
6. Navigate to the ZErO prompt of the configuration loop by pressing the decrement button repeatedly. When the ZErO
prompt appears, press the enter button.
7. Adjust the value shown on the numeric display to the desired value, usually 0. Press the enter button to accept the
value. CAUTION! If you fail to press the enter button the new calibration value will not be saved.
8. If necessary, navigate to the FULL prompt and press the enter button. Adjust the current to achieve end scale single
phase test watt indication on the standard watt meter.
9. Scroll the BarGraph’s indicated end scale value to the desired end scale value, using the increment or decrement
buttons. Press the enter button to accept the new value. CAUTION! If you fail to press the enter button the new
calibration value will not be saved.
If the BarGraph being calibrated is NOT a self contained var meter (type BGV), calibration is complete. Skip down to step
15.
10. Set the calibrator to indicate vars. Energize the test circuit and adjust the potential to the BarGraph’s rated voltage.
Adjust the current output to zero and shunt the current inputto the test circuit. The standard should be indicating zero
vars.
11. If the type BGV BarGraph is set up for left zero (only left most LED is lighted with zero vars applied) navigate to the
ZErOprompt of theconfiguration loopby pressingthe decrementbutton repeatedly.When the ZErOpromptappears,
press the enter button. Scroll to 0 on the BarGraph numeric display, then press the enter button again. CAUTION! If
you fail to press the enter button the new calibration value will not be saved. Skip down to step 13.
12. If the type BGV BarGraph is set up for center or offset zero, remove the shunt from the current source. Adjust the
phase shifter until the phase angle meter indicates -90E, then adjust the current until the var standard indicates the
leftendscalesinglephasetestwatts.NavigatetotheZErOpromptoftheconfigurationloopbypressingthedecrement
button repeatedly. When the ZErO prompt appears, press the enter button. Scroll the BarGraph numeric display to
the desired indicated value, then press the enter button. CAUTION! If you fail to press the enter button the new
calibration value will not be saved.
13. Adjust the phase shifter untilthe phase angle indicates +90E. Adjust the current until the standard var meter indicates
full scale (or right endscale) single phase test watts. Navigate tothe FULLprompt ofthe configurationloop. Whenthe
FULLpromptappears,presstheenterbutton.ScrolltheBarGraphnumericdisplaytothedesiredindicatedvalue,then
press the enter button. CAUTION! If you fail to press the enter button the new calibration value will not be saved.
14. Re-check left and right end scale indications using the above steps, without pressing any programming buttons.
15. De-energizethecalibrationcircuitand turn off thetestequipmentand the BarGraph. ReplacetheBarGraphcoverand
return it to service.
OMBGP100 Rev 1 Page 17 of 23

7.0 Troubleshooting
TheACP4seriesBarGraphs are designed fortroublefreeservice, but it is acknowledgedthat power systemsarecomplex
circuitsandproblemswhich result in erroneousindicationscanbe very frustratingtotroubleshoot.Thissectionisintended
to help eliminate the BarGraph as a source of any problems.
Operational problems can be segregated into three general conditions; failure to operate, inaccurate indication and
erroneous display.
Failure to Operate
Failure to operate is characterized by a lack of display illumination. This is typically caused by lack of adequate power or
a blown fuse. Check the power source requirement on the BarGraph’s data plate and measure the power that is applied
to be sure that it is adequate. Compare the measured power level to the power requirement listed in the specifications
section of this manual, for your BarGraph. If the power source is adequate, check the fuse. If it is inadequate, correct the
problem before continuing.
The fuse is mounted on the I/O module inside the rear of the instrument. On instruments with the standard base, the fuse
protrudes through the base plate and is readily accessible from the rear. Refer to figure 3 for its location. On instruments
with the molded base, the fuse is not readily accessible. The unit must be removed from the panel, then removedfrom the
case in order to accessthe fuse. The fuse is socketed, and may be removed by simply pulling straight out. The orientation
of the pin sockets are as indicated in figure 3. The pins of the fuse are likewise oriented in parallel with a line marked on
the face of the fuse.
The fuse ratings and part numbers are given in tables 3A, 3B and 3C. When referring to the tables, be sure you have the
correct type (Standard, Enhanced or TriColor).
Table 3A Fuse Ratings and Part Numbers for Standard BarGraphs
Power Supply Voltage Fuse Rating
(A) Weschler Part Number Manufacturer Manufacturer’s Part Number
12 vdc 1.6 4300000316 Wickman 374-1160-041
24 vdc 1.0 4300000314 “ 374-1100-041
28 vdc 1.0 4300000314 “ 374-1100-041
48 vdc 0.8 4300000313 “ 374-0800-041
125 vdc 0.5 4300000311 “ 374-0500-041
250 vdc 0.25 4300000308 “ 374-0250-041
120 vac 0.5 4300000311 “ 374-0500-041
240 vac 0.25 4300000308 “ 374-0250-041
Universal
120 vac / 125vdc 0.5 4300000311 “ 374-0500-041
Table 3B Fuse Ratings and Part Numbers for Enhanced BarGraphs
Power Supply Voltage Fuse Rating Weschler Part Number Manufacturer Manufacturer’s Part
Number
12 vdc 1.6 4300000316 Wickman 374-1160-041
24 vdc 1.0 4300000314 “ 374-1100-041
28 vdc 1.0 4300000314 “ 374-1100-041
48 vdc 0.8 4300000313 “ 374-0800-041
125 vdc 0.5 4300000311 “ 374-0500-041
250 vdc 0.25 4300000308 “ 374-0250-041
120 vac 0.5 4300000311 “ 374-0500-041
240 vac 0.25 4300000308 “ 374-0250-041
Universal
120 vac / 125vdc 0.5 4300000311 “ 374-0500-041
OMBGP100 Rev 1 Page 18 of 23