Operation 57

3.1.7 Load TransferProcedures Screen

Goto the SCC Master Menu and move the highlighted cursor to LOAD TRANSFER PROCEDURES. Note

thatthis screen is displayed at the System Control Cabinet but is notre quiredat the UPS modules. Press the

Selectpad and the Load Transfer Procedures screen is displayed.

TheLoad Transfer Procedures screen contains instructionsto transfer the critical load between the UPS system

andthe bypass line. Comparisons of the UPS and bypass voltage, frequency,and phase synchronization are dis-

playedalong with transferstatus messages and an indicationof circuit breakeroverlap time. The metered param-

etervalues on the Load Transfer Procedures screen are updated at half-second intervals.

Refer to 3.3.2 - Load TransferP roceduresfor more details.

Figure 36 Load Transfer Procedures Screen

Item1 - Voltage Comparisons. This chart shows the UPS and bypass voltageand frequency comparisons

betweeneach of the three phases. If the UPS and bypass voltagesare not within specified tolerances, a manual

transferis not permitted and TRANSFER PROHIBIT is highlighted.

TheVoltage Adjust knob (push-to-turn),located on the SCC Operator Control Panel (Figu re 10), is used to

matchthe UPS output voltage to the bypass voltage. When the UPS and bypass voltagesmatch within the spe-

cifictolerance, a manual transfer is possible and OK TO TRANSFER is highlighted.

Item2 -Synchronization. This display shows the phase synchronizationbetween the UPS output and bypass

power.If the phase displacement is outside of the tolerance, a manual transferis not permitted and TRANS FER

PROHIBIT is highlighted.

Duringnormal operation, the synchronization display should read UPS LEAD from zero to 4 degrees.

Item 3 - Status Messages. Three messages are constantlydisplayed here. Only the active message is high-

lighted. If TRANSFER PROHIBIT is highlighted, manual transfers/retransferscannot be performed, and auto-

maticretransfers will not be initiated.

Item4 -Manual Transfer Instructions. These instructions assist the operator intransferring the critical load

betweenthe UPS system and the bypass line.

Ifthe load is on the bypass line, step 2 on the screen will instruct you to press the UPS and Control Enable but-

tonsto retransfer the load from the bypass line to the UPS system.

CAUTION

TheUPS output voltage responds very slowly to inputs from the VoltageAdjust

knob.Make small adjustments and wait several seconds each time for voltage to

stabilizebefore continuing.

OUTPUTVOLTS
OUTPUTAMPS
OUTPUTFREQUENCY
LOADKVA
BYPASSVOLTS
A
380
530
380
DC
B
380
530
380
TIMELOAD
349
C
380
530
380
HERTZ
50.0
NEXTFRAME
PREVIOUSFRAME
EXIT
UP :
DOWN :
SELECT :
HISTORY STATUS MODULE-0 04/10/97 16:49:21 FRAME 36
ORDER- 0 00000 SITE ID - 0000 0 SITETAG - 0000000
****ACTI VE ALARMS **** Output Ov-volts
OUTPUTVOLTS
OUTPUTAMPS
OUTPUTFREQUENCY
OUTPUTVOLTS
OUTPUTAMPS
BATTERYVOLTS
OUTPUTVOLTS
OUPUTAMPS
BATTERYAMPS
INPUTVOLTS
INPUTAMPS
OUPUTVOLTS
OUTPUTAMPS
LOADKVA
A
380
410
380
410
380
410
0
0
380
410
DC
390
-583
B
380
410
380
410
380
410
0
0
380
410
TIME
0:01
LOAD
270
C
380
410
380
410
380
410
0
0
380
410
HERTZ
50.0
NEXTFRAME
PREVIOUSFRAME
EXIT
UP :
DOWN :
SELECT :
HISTORY STATUS MODULE-0 01/17/98 11:21:59 FRAME 100
ORDER- 0 00000 SITE ID - 0000 0 SITETAG - 0000000
****ACTI VE ALARMS **** Batt Dischargin g LowBatt Warn ing
TRANSFERPROHIBIT
UPS LE AD = 2 Deg
UPS -
BYPASS -
480480
480481
B-CA-B
VOLTAGECOMPARISON
SELECT : MASTERMENU
OK TO TRANSFER
+30
ONUPS
60.0Hz
479
C-A FREQUENCY
MANUAL
TRANSFERINSTRUCTIONS
1. AdjusttheUPS voltage until it equals the
bypassvoltage with the VOLTAGEADJUST pot.
2. Ifthe OK TOTRANSFER message is highlighted,
simultaneouslypress theBYPASS andCONTROLENABLE
buttons.
3. Verifythatthe transfer was successfulby checking the
breakerstatus on the "MONITOR/MIMIC"screen.
4. PresstheALARM RESET button to clear alarms which
areno longer active
SYNCHRONIZATION
60.0Hz
0-30
480
12
4
3
DISCONTINUED
PROD U C T