Megger SR-98 User manual

Part _51128
Date 01/25/2006
INSTRUCTION MANUAL
For
RELAY TEST SET
Model SR-98
The SR-98 includes a ROM-resident computer program. This program
belongs to Megger Corporation and contains trade secret ideas and
information of Megger Corporation. To the extent this program contains ideas,
Megger Corporation intends to protect and enforce its rights under state law.
To the extent the program is deemed to constitute a form of expression of
idea, Megger Corporation intends to protect and enforce its rights under the
Copyright Act of 1976. The Statutory Copyright notice has been affixed hereto
in the event that it is later determined that the program has been published
within the meaning of the Copyright Act of 1976.
It is essential that this instruction book be read thoroughly before
putting the equipment in service.

REVISION HISTORY
Revision ECN # Date
0 Initial Release 11/19/1998
1 28954 07/31/2001
2 29143 12/20/2001
3 29447 11/20/2002
4 30248 01/25/2006
COMMENTS
Any comments or suggestions regarding the use of this test instrument or
instruction manual would be appreciated. Send your comments to Megger, T M &
S Department, 4271 Bronze Way, Dallas, TX 75237
IMPORTANT
The information and data contained within this instruction manual are proprietary
with Megger. The equipment described herein may be protected by one or more
U.S. letters patent. MEGGER specifically reserves to itself all rights to such
proprietary information as well as all rights under any such patent, none of which
is waived by the submission of this instruction manual to anyone.
The recipient, if a Government agency, acknowledges that this instruction book
and the equipment described were procured with "Limited Rights" to technical
data as described in ASPR 9-203 (b).
Copyright Megger, 1998, 2001,2006

SAFETY PRECAUTIONS
WARNING:
VOLTAGES GENERATED BY THIS INSTRUMENT CAN BE HAZARDOUS
This instrument has been designed for operator safety; however, no design can completely
protect against incorrect use. Electrical circuits are dangerous and can be lethal when lack
of caution and poor safety practices are used. There are several standard safety precautions
that should be taken by the operator. Where applicable, IEC safety markings have been
placed on the instrument to notify the operator to refer to the instruction manual for
instructions on safety related topics. Refer to the following table of symbols and definitions.
Symbol Description
Direct Current
Alternating Current
Both direct and alternating current
Ground terminals are connected to chassis ground.
Protective Conductor Terminal
Frame or Chassis Terminal
On (Supply)
Off (Supply)
Caution, risk of electric shock
Caution (refer to accompanying documents)

SAFETY PRECAUTIONS CONTINUED
The following are some specific safety related items associated with the SR-98 test
system.
Always start with the power OFF, before connecting the power cord. Make sure outputs
are off before attempting to make test connections.
Always use properly insulated test leads. The test leads supplied with the unit are rated
for the voltage output ratings of the test system, and should be properly used and cared
for. Do not use cracked or broken test leads.
Always lift and carry the test set using both carry handles. Improperly carrying the unit
by one handle could damage the handle.
Always turn the test system off before disconnecting the power cord. Turn outputs off
before removing or inserting test leads.
UNDER NO CIRCUMSTANCES SHOULD THE OPERATOR PUT HIS HANDS OR TOOLS
INSIDE THE TEST SYSTEM CHASSIS WITH THE TEST SYSTEM CONNECTED TO A
POWER SOURCE. LETHAL VOLTAGES ARE PRESENT AND MAY CAUSE SERIOUS
INJURY OR DEATH!
INSTALLATION Category II
OPERATIONAL SAFETY
Every consideration has been given to the design and construction of the SR-98 to
make it a safe piece of test equipment as well as one that is accurate, reliable and easy
to use.
It must be remembered that the unit is capable of producing voltage and current levels
that can be deadly if personnel come in contact with them.
The SR-98 unit should be properly operated and serviced by qualified individuals who
have familiarized themselves with the unit and thoroughly read the instruction manual
provided with it.
If questions arise concerning care, operation or application of the unit that are not
explained in the instruction manual, contact an MEGGER representative.

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TABLE OF CONTENTS
THEORY OF OPERATION...........................................................................................................................1
UNIT PANEL ILLUSTRATION........................................................................................................1
DESCRIPTION OF CONTROLS AND INSTRUMENTATION.....................................................................2
INPUT POWER................................................................................................................................6
DISPLAY SCREENS.......................................................................................................................8
POWER UP SCREEN ........................................................................................................8
TEST MENU Screen ..........................................................................................................8
ABOUT MENU....................................................................................................................9
LANGUAGE SELECTION Screen.....................................................................................9
TIMER SETUP Screen.....................................................................................................10
DESCRIPTION OF TEST SCREENS............................................................................................12
CURRENT RELAY Test Screen......................................................................................13
IMPEDANCE RELAY Test Screen..................................................................................16
DIRECTIONAL RELAY Test Screen...............................................................................17
DC RELAY Test Screen..................................................................................................17
METERING Screen..........................................................................................................18
VOLTAGE RELAY Test Screen......................................................................................18
POWER RELAY Test Screen..........................................................................................19
SYNC (Synchronizing) RELAY Test Screen.................................................................20
RECLOSE RELAY Test Screen......................................................................................21
TIMER RELAY Test Screen............................................................................................21
SELECTION OF OUTPUT TERMINALS....................................................................................................22
CURRENT MAIN ...........................................................................................................................22
AC AUX and DC AUX...................................................................................................................22
SELECTION OF MASTER UNIT................................................................................................................23
SERVICE DATA .........................................................................................................................................24
MAINTENANCE INSTRUCTIONS ................................................................................................24
BASIC TROUBLESHOOTING......................................................................................................24
ALARM DESCRIPTIONS..............................................................................................................27
WARRANTY..................................................................................................................................29
TEST APPLICATIONS...............................................................................................................................30
TEST PROCEDURES.................................................................................................................................30
TIME DELAY OVERCURRENT DEVICES ...................................................................................30
INSTANTANEOUS ELEMENT OF OVERCURRENT RELAYS...................................................33
DC TARGET AND SEAL IN..........................................................................................................34
IMPEDANCE RELAY ....................................................................................................................35
VOLTAGE RELAY.........................................................................................................................37
DIRECTIONAL RELAY .................................................................................................................39
POWER RELAY ............................................................................................................................41
SYNC (Synchronizing) RELAY....................................................................................................44

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RECLOSING RELAY ....................................................................................................................47
DC RELAY.....................................................................................................................................48
METERING FUNCTIONS..............................................................................................................51
TIMER............................................................................................................................................52
TESTING CURRENT DIFFERENTIAL RELAYS..........................................................................54
TESTING PHASE SEQUENCE UNDERVOLTAGE RELAYS......................................................61
MOLDED CASE CIRCUIT BREAKERS .......................................................................................66
TIMING TEST OF MOLDED CASE CIRCUIT BREAKERS .........................................................67
MOTOR OVERLOAD RELAYS.....................................................................................................69
PARALLEL PRINTER PORT.....................................................................................................................70
RS232 SERIAL DATA PORT.....................................................................................................................70
SR-98 COMMAND SET..............................................................................................................................71
SPECIFICATIONS......................................................................................................................................76
PARTS LIST ...............................................................................................................................................86

1
THEORY OF OPERATION
The MEGGER SR-98 relay test set is a portable, self-contained unit, which provides
continuously adjustable current and voltage outputs, with phase shifting capability and
harmonic output currents for testing a wide variety of protective relays.
The unit is housed in a rugged, compact suitcase-type thermoplastic enclosure with
convenient carry handles and removable cover.
The SR-98 unit incorporates a microprocessor-based digital metering display, which
displays AC and DC Amperes, AC and DC Volts, and Time in both Seconds and Cycles.
Depending on type of test selected, other values may be displayed, such as Ohms,
Watts, VARS, Phase Angle, Frequency or Power Factor.
The independent outputs enable the SR-98 to provide an ac current, voltage (both ac
and dc), or two ac voltages and a dc voltage, to meet numerous testing requirements in
a wide variety of test applications. The main AC current output has selectable output
ranges of 4 Amperes @ 0 - 230 Volts; 10 Amperes @ 0 - 90 Volts; 45 Amperes @ 0 -
20 Volts and 115 Amperes @ 0 - 8 Volts, at selectable frequencies. The AC and DC
voltage outputs are independent and switch selectable. The AC voltage has a range of
0 - 300 Volts @ 0.25 Amps. The DC voltage has a range of 0 – 250 V @ 0.4 Amps.
UNIT PANEL ILLUSTRATION

2
DESCRIPTION OF CONTROLS AND INSTRUMENTATION
RS232 Serial Port (1):
This 9-pin connector can be directly interfaced to a computer terminal, a serial data
acquisition system, or a COM port on any personal computer. Required for use of
MEGGER Software. See RS232 Serial Data Port for more information on the use of
the port.
Interface Terminal (2):
This interface terminal provides a 10 to 30 Volts AC output to a voltage coil of a phase
angle meter. It should be noted that the voltage output is in-phase with the SR-98 main
AC current output. DO NOT apply this voltage output to the current coil of a Phase
Angle Meter. Optional interface cables are available to interface with MEGGER phase
shifters models EPS and PVS-1000, see Optional Accessories in Specifications. This
interface port may also used to connect two SR-98’s together for testing the slope
characteristics of current differential relays, and to do harmonic restraint tests on
transformer differential relays. When interconnected, there will not be more than a ± 3º
phase shift between the two main current outputs (same output taps). An optional
interface cable is available to interface two SR-98 units together, see Optional
Accessories in Specifications.
Parallel Printer Port (3):
The parallel printer port can be connected to any dot matrix, Centronix compatible
printer. Used in conjunction with the PRINT SCRN button, it allows the user to print
metered values / Test Results from the test screen directly to a printer. See Parallel
Printer Port Section for more information about the port.
RECLOSING RELAY Reset Fuses 1A (4):
Protects the reclosing relay A/B contacts of the test set. If this fuse is tripped, the unit
A/B contacts will not operate. If Fuse trips, check test circuit for cause of inappropriate
current. Reset fuse by pressing down on fuse reset button.
RECLOSING RELAY A and BTerminals (5):
These two sets of relay contacts, one Normally Closed (A) and one Normally Open (B),
work in conjunction with the Reclosing Relay Test Screen to simulate the opening and
closing of circuit breakers.

3
TIMER START/STOP MONITOR Terminals (6):
Two identical, independent, terminals are provided to monitor operation of relay
contacts or trip SCR’s. See TIMER SETUP SCREEN for detailed descriptions of
available modes of operation.
RESISTOR BANK, 2A, 10A, 15A Terminals (7):
Three terminals are provided. Output current from the SR-98 may be series through the
resistor elements. Labeling shows maximum current for which the resistors are rated.
See SELECTION OF OUTPUT TERMINALS, CURRENT MAIN for use and ratings.
Input Power Connection (8):
The input connector is a standard IEC connector. See Input Power for description of
power input and power cord selection.
Protective Ground (Earthing) Terminal (9):
Use this terminal to connect the chassis ground to earth ground.
INPUT FUSES (F1, F2) (10):
Input fuses are located on the backside of the top cover next to the input power
connector. They protect the input power portion of the test set. If this fuse is blown, the
unit will not operate. Fuse should be replaced with appropriate size, slow-blow, T rated
fuses (see accessory list).
CURRENT MAIN Output Binding Posts (11):
In conjunction with the common tap, four current rated output binding posts are provided
to supply a variety of currents at various voltage levels. The output is controlled by the
Control Knob (18). See Selection of Output Terminals for further description.
WARNING: Do not use more than one current-rated tap at a time and only in
conjunction with the common tap, never with each other. Some of the output
terminals present a shock hazard, the user should take appropriate safety measures
when the output is on. Never handle the test leads when the output is on.
OUTPUT ON Lamp (12):
Lights up whenever the AC current output terminals, CURRENT MAIN, are energized.

4
MEASUREMENT INPUT Terminals (13):
Two sets of terminals are provided. The V, voltage terminals, is used to measure
external AC or DC voltages up to a maximum of 600 Volts. The I, current terminals, is
used to measure external AC or DC currents up to a maximum of 6 amperes.
Caution: Use properly rated CATII insulated test leads with the MEASUREMENT
INPUT and AC or DC AUX voltage output terminals, part number 684000 and
684001 (see accessory list).
AC AUX Voltage Output Terminals (14):
These output terminals are used to provide AC voltage to the device under test. The
output is controlled by the Control Knob (18).
0 - 300 VAC MAX: Up to 300 Volts AC is available from these terminals.
Warning: Lethal voltages present when outputs are on
DC AUX Output Terminals (15):
These output terminals are used to provide DC voltage or DC current to the device
under test. The output is controlled by the Control Knob (18).
0 - 250 VDC MAX : Up to 250 Volts DC is available from these terminals.
0 – 2.5 ADC MAX : Up to 2.5 Amperes DC is available from these terminals.
Note: DC voltage is available from all Relay Test Screens. The selection of either
voltage or current is made from the DC Relay Test Screen.
AC and DC Voltage Switches (16):
The AC or DC Voltage Switches control the AC AUX and DC AUX voltage outputs, on
and off. When either AC or DC voltage outputs are on, the lamp in the switch will be lit.
While in the ON position, the outputs stay on regardless of the state of the INIT Switch
(24). When testing Voltage Relays, the AC Voltage is dynamically changed from the
NORMAL to the FAULT Voltage when the INIT Switch is pressed. When the relay
operates the AC voltage output is turned off (see Voltage Relay Test Procedure).

5
Hardware Reset Button (17):
This small recessed button is used to reset the hardware. In case of a total system
shutdown, this button may be pressed to reset the hardware without switching the
power on/off switch.
Rotary Control Knob (18):
The rotary knob rotates clockwise and counterclockwise to affect the highlighted field on
the display screen. It provides continuous, variable, control of the selected output.
Used to control the amplitudes of the CURRENT MAIN, AC AUX and DC AUX outputs.
It may also be used to vary the Phase Angle between the AC AUX and CURRENT
MAIN outputs. It may also be used in conjunction with the Cursor Arrow Keys to
change default settings to the Timer and other control functions. For example, using the
cursor arrows, a function like Ramp may be highlighted. Rotating the knob either
direction changes the selected ramp rate from Normal to Fast to Slow back to Normal.
POWER ON/OFF Switch (19):
The switch controls the input power to the unit. Power on is indicated by the meter
display, which will light up when the unit is energized.
Digital Display (20):
The digital display is a LCD panel with a resolution of 128 X 256 pixels. It indicates
metered quantities of ac and dc current, ac and dc voltages, and Time in both Seconds
and Cycles. Depending on type of test selected, other values may be displayed, such
as Ohms, Watts, VARS, Phase Angle, Frequency or Power Factor. The metered
readings are auto-ranging. In addition, the display also allows the user to select other
features using the Function Buttons located directly below the display. See Display
Screens for description of available functions.
ALARM RESET Button (21):
In the event of a thermal overload, output overload, or a Power Factor Corrector (PFC)
overload, the test set will protect itself and shut down operation. An overload message
will be displayed on the screen indicating what caused the alarm. See ALARM
DESCRIPTIONS under SERVICE DATA for more information. To reset , press this
button. This is also referred to as a software reset.
TRIP light (22):
Works in conjunction with the STOP/MONITOR Terminals. The TRIP lamp will glow,
when the condition set with the TIMER SETUP, STOP/MONITOR Mode is met.

6
SYNC light (23):
When unit is synchronized to the power line source, this lamp will be lit. The line
synchronization is selected from the Timer Setup Screen, see Out Freq. description.
INIT (INITIATE) Button (24):
The INIT Button serves to initiate (turn on) the CURRENT MAIN output of the test set.
In addition, it also serves to initiate certain test functions like a timing test on voltage
relay.
PRINT SCRN Button (25):
This button is used in conjunction with the Parallel Printer Port to print the metered / test
values from the display screen.
Up, Down, Right and Left Arrows (26):
These arrows move the graphic screen highlighted function up, down, right and left on
the screen. It works in conjunction with the rotary knob to change the highlighted
function.
INPUT POWER
There are two versions of the SR-98. One is rated for 230 volt operation only. The
other has a universal input of 90 to 253 volts, 1700 VA max.
Model SR-98-1/60 comes with a universal power input (90 - 253 VAC, 50/60 Hz input),
a north American power cord and firmware set to default to 60 Hz output on power up.
Model SR-98-2/50 comes with a universal power input (90 - 253 VAC, 50/60 Hz input),
a international color coded power cord and firmware set to default to 50 Hz output on
power up. Model SR-98-3/50 has a power input of 230 volt only (230 VAC, 50/60 Hz
input), a Continental Europe power cord and firmware set to default to 50 Hz output on
power up.

7
The SR-98-2/50 come with a standard 10 Amp, International Color code power cord as
shown below. The cord is ready for wiring to the appropriate plug (depending on
country). The following colors apply, Brown = Line, Blue = Neutral and Green/Yellow =
Ground.

8
DISPLAY SCREENS
POWER UP SCREEN:
The first screen that the operator will see after switching the unit on is the Power Up
Screen.
Using the associated Function keys at the bottom of the display screen, the user can
select the Test Menu, the About Screen, Language Select Screen or Master Slave
Select (change the screen contrast with the UP/DN arrow keys).
TEST MENU Screen:
The Test Menu Screen allows the user to select which type of relay to test, metering or
timing function. Using the arrow keys, highlight to the desired relay or function and
press the SELECT function key at the bottom-right of the screen. To return to the
Power Up screen, press the PREV SCREEN function key at the bottom-left of the
display screen.

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ABOUT MENU:
The About Menu displays the firmware Version Number, with date of release, along with
the Copyright, see Copyright statement on front page of manual.
LANGUAGE SELECTION Screen:
This screen allows the user to select the desired operating language of the test set.
Using the arrow keys, highlight to the desired language and press the SELECT function
key at the bottom-right of the screen. To return to the Power Up screen, press the
PREV SCREEN function key at the bottom-left of the display screen.

10
TIMER SETUP Screen
The TIMER SETUP screen is used to set the Timer Start and Stop/Monitor Options,
set the Start and Stop Latch Options, set Output Frequency, turn the Monitor Horn
on and off and set the Delay Cycles for momentary operation.
The user may use the arrow keys and the rotary knob to move from function to function
and change the option. The following are descriptions of each option and function of
the TIMER SETUP Screen.
The following modes are provided for the START and STOP/MONITOR gates:
V. APPL (Voltage Applied):
Used when doing a timing test. The function of this position is to monitor the
application of an AC/DC voltage across the trip output of the device under test.
The Timer starts or stops when an AC potential (60 - 300 Volts RMS) or DC
potential (5 - 300 Volts) is applied. Note: CATII insulated test leads required
(use PN684000 and 684001 leads).
V. REMOV (Voltage Removed):
Used when doing a timing test. The function of this position is to monitor the
removal of an AC/DC voltage across the trip output of the device under test. The
Timer starts or stops when an AC potential (60 - 300 Volts RMS) or DC potential
(5 - 300 Volts) is removed. Note: CATII insulated test leads required (use
PN684000 and 684001 leads).
N. OPEN
(Normally Open):
The function of this position is to monitor normally open dry contacts of the
device under test. The Timer starts or stops at the closing of a normally open dry
contact.

11
N.CLOSE (Normally Closed):
The function of this position is to monitor normally closed dry contacts of the
device under test. The Timer starts or stops at the opening of a normally closed
dry contact.
INIT (Initiate):
When the
TIMER START Mode is in this position, the Timer will start when the
output, or test, is initiated using the INIT Button.
DE-INIT (De-initiate):
When the contacts close on the timer start terminals, the output current is de-
initiated and the timer is started. The trip contacts are monitored by the start
terminals and the contacts associated with the back-stop are monitored with the
stop terminals, see Overcurrent Relay, Run-back Test for more details.
CURR X (Current Actuate):
This option is associated with the Stop/Mon function. The Timer stops when the
device under test interrupts the CURRENT MAIN output. The CURR X
position is used when the device under test has no contacts other than those
used to pass current (such as a single-pole circuit breaker).
NOTE: Output must be maintained above threshold level or timer error will result.
MON (C)
(Monitor Continuity):
The function of this position is to monitor the change of state of normally open or
closed dry contacts of the device under test. The TRIP lamp will light at the
closing of a normally open dry contact. If the Horn is turned on, then the horn will
sound when the contacts close.
MON (V)
(Monitor Voltage):
The function of this position is to monitor the change of state of an AC/DC
voltage output from the device under test. The TRIP lamp will light at the
applying of a AC potential (60 - 300 Volts RMS) or DC potential (5 - 300 Volts)
voltage. If the Horn is turned on, then the horn will sound when the voltage is
applied. Note: CATII insulated test leads required (use PN684000 and 684001
leads).
LATCH ON/OFF:
This mode is used in conjunction with the selected START/STOP options and the
START/STOP Terminals to supervise the starting and stopping of the Timer.
START LATCH:
The Timer
START LATCH ON allows timing to be initiated by a Start Gate and to
be stopped only by the selected Stop Gate. When unlatched, LATCH OFF,
allows timing to be stopped when the Start Gate is reversed (such as when
timing the closing and opening of a single contact as in measuring the trip-free
operating time of a circuit breaker).

12
STOP LATCH:
When the
STOP circuit is latched ON, the stop latch allows timing to be stopped
at the first operation of any selected stop gate. When the STOP circuit is latched
OFF, the stop latch allows timing to be stopped by any stop gate and then
restarted if the stop gate reverses (provided a start gate is still energized) and
stopped when the stop gate is again true. NOTE: When using the MONITOR
feature, the STOP LATCH must be OFF.
Out Freq.:
Based on the Model number of the unit, this value will default to either 60 HZ or 50 HZ.
If another output frequency is desired (other than the default) for the CURRENT MAIN
output, the user highlights this value and rotates the Control Knob either clockwise to
increase or counter-clockwise to decrease the value. Output frequencies available are
16.66, 25, 33.3, 50, 60, 100, 120, 125, 150, 180, 250 or 300 Hz. In addition, to
synchronize the CURRENT MAIN to the input line source, select 60 Hz SYNC or 50 Hz
SYNC. Once selected the SYNC light on the front panel will be lit. The output current
will be in-phase with the line voltage, ±5 degrees, depending on which output tap is
selected and the test current set. Note: The higher output taps results in less phase
error.
Mon Horn:
The user can select to turn the Monitor Horn ON or OFF. The horn sounds when the
relay contacts close. In the event that the contacts are normally closed, the horn would
sound continuously, until they are opened. The default setting is Horn OFF. To
change, press HORN ON/OFF button to turn ON.
Del Cycles:
Used in conjunction with the INIT button and the MODE SELECT button, the user can
select the number of cycles that the CURRENT MAIN output will be on. The MODE
SELECT button at the bottom of each Test Screen controls whether the output is in the
MOM. (MOMENTARY) mode, or the MAINT. (MAINTAIN Mode). If in the MOM. mode,
the output will only be on for the Del. Cycles setting. For example, the default is 4
cycles. This means that the output will be ON for approximately 4 cycles. This value
may be changed up to 10 cycles by using the arrow keys to highlight the value and
rotating the control knob to the desired number of delay cycles.
DESCRIPTION OF TEST SCREENS
The following descriptions apply to the different Test Screens that appear in the TEST
MENU Screen. There are common Amplitudes, Features and Function Buttons
associated with many of the screens. These Amplitudes, Features and Function
Buttons will be described only one time, with the CURRENT RELAY Test Screen.
Other Values, Features or Function Buttons that are unique to an individual Test Screen
will be described with the associated screen description.

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CURRENT RELAY Test Screen
The CURRENT RELAY Test Screen is used for testing all overcurrent, voltage
controlled overcurrent, voltage restrained overcurrent and other AC current controlled
relays, including motor overload relays and small molded case circuit breakers. If
testing directional overcurrent, see DIRECTIONAL RELAY Test Screen.
The following are descriptions of each of the displayed values, features or functions in
the CURRENT RELAY Test Screen.
AC AMPERES ( 00.0% ): The value displayed is the measured output current from the
CURRENT MAINS output terminals. The (%) value displayed provides a reference
point for setting test current quickly and easily. The current can be adjusted in
approximate proportion to the % displayed. This is a big time saver when testing similar
relays with the same tap settings. However, there is an advantage that is different from
the old SR units, it's virtually linear. Let’s say you want to do multiple timing points on
the same relay. For example, you wish to test at 2, 4 and 6 times the tap rating of the
relay (this only works if you use the same CURRENT MAINS output tap for all tests).
When you set your test current for the first test point, let's say the % indication is 8 %.
To quickly adjust the test current for the next point (4 X), adjust the % indication to 16
%, go to the Momentary Mode, a give it a shot. The test current should be very close to
the desired test current. For the next point, adjust to 32 %. This does not account for
voltage drop in the test leads at high current values. Make sure you use the 6 mm test
leads. You might have to make a small adjustment to get the exact test current you
desire. But it does save time compared to the old hunt and peck, "jogging" method used
on the old style SR units. And, it reduces heat in the relay and the test set, since you're
not reapplying multiple shots of test current "hunting" for the proper setting. When
rotating the Control Knob, the % value changes up or down depending on the direction
of rotation.
AC VOLTS ( 00.0 V ): The value displayed is the measured output voltage from the AC
AUX output terminals. The voltage value displayed in the ( 00.0 V ) is the estimated
output for the selected output terminal. The actual output voltage may vary slightly
depending on the actual load. This allows the operator to preset a voltage output
without turning the voltage on. When rotating the Control Knob, the voltage value
changes up or down depending on the direction of rotation

14
DC VOLTS ( 00.0 V ): The value displayed is the measured output voltage from the DC
AUX output terminals. The voltage value displayed in the ( 00.0 V ) is the estimated
output for the selected output terminal. The actual output voltage may vary slightly
depending on the actual load. This allows the operator to preset a voltage output
without turning the voltage on. When rotating the Control Knob, the voltage value
changes up or down depending on the direction of rotation.
SEC / CYCLES: The time displayed in the SEC (seconds) display area is the operating
time of the device under test in seconds. The value displayed in the CYCLES display
area is the operating time in cycles based normally on either a 60 Hz or 50 Hz time
base. The time base depends on the base frequency set in the Timer Setup Screen
(see Timer Setup Screen for details on Frequency changes).
60 or 50 Hz: The frequency displayed in the upper right corner of the display screen
indicates the output frequency of the CURRENT MAIN and AC AUX output (see OUT
FREQ. Under Timer Setup Screen). It also indicates what the base frequency is for
timing in Cycles (see SEC/CYCLES above).
Ramp: There are three speeds at which the output can change when rotating the
Control Knob. They are, Normal, Slow and Fast. To change the Ramp speed, use the
cursor arrows to highlight the Ramp window. Rotating the knob either direction
changes the selected ramp rate from Normal to Fast to Slow back to Normal. Once
selected, use the arrow keys to cursor back to the amplitude value that you want to
change and rotate the Control Knob.
Meter: There are two selections for metered values. They are RMS (Root Mean
Squared) or PEAK. The highlighted, metered value displayed can be either of these
two selections. Normally, RMS is required, therefore the defaulted value displayed is
RMS. To change, use the cursor arrows and control knob similar to that described
above for Ramp.
Mode: There are three selections for the mode of operation. They are MOM
(momentary), MAINT (maintain) and CA (current actuate). In the MOM mode the
CURRENT MAIN is turned on momentarily for the Delay Cycles time period, which is
defaulted to 4 cycles (see Timer Setup Screen for description of Delay Cycles). This
feature can be changed from MOM to MAINT by pressing the MODE SELECT function
button at the bottom of the screen, see MODE SELECT for description of operation.
START: NONE LATCH
STOP: MON(C) LATCH : Indicators of the Timer START and STOP gate settings
(see Timer Setup Screen for details of settings). These indicators aid the operator in
knowing what the setup is for the Timer without needing to go to the Timer Setup
Screen. To change the settings, press the TIMER SETUP function button at the bottom
of the screen.