Manual Bring-Up Of The Dc Power; Power Supply Voltages - IBM System/32 Introduction And Maintenance Manual

8.2.8 Manual Bring-Up Of The DC Power
Supply
In troubleshooting some power supply problems,
it might be advantageous to bring up the dc power
supply manually.
However, the following precautions must be observed
when manually brining up the dc power supply.
CAUTIONS
• If your problem is overcurrent or overvoltage,
do not use this procedure.
• If the system has a belt printer, disconnect P6
to prevent possible damage to the hammer
driver cards. For P6 location, see page 4-77.
• Do not unload the +8.5 Vdc or -5 Vdc singly;
they must be unloaded together to prevent
damage to the F ET logic.
• With the power supply up, any error detected
does not bring down the power supply.
8.2.9 Power Supply Voltages
To manually bring up the dc power supply sequence:
1.
2.
3.
4.
5.
Turn power off at the operator control
panel. After the power is sequenced down,
turn the mainline switch off.
Remove the power sequence card.
Connect a jumper wire from M08 to P05
(-pick K1) on the power sequence card
socket.
Turn the mainline switch on. The fans
should start and K1 should energize,
bringing up the dc power supply.
Measure filter assembly voltage levels.
8-20
Notes:
1. If a short in the load is suspected, the filter
assemblies are capable of operating with all
load connections removed (that is, E3, E4,
and E5).
2. With all load connections removed, a filter
assembly voltage levels may vary approximately
±20% from normal voltage.
6. Turn the mainline switch off.
7.
8.
9.
Remove the jumper wire from pin M08
to pin P05.
Reinstall the power sequence card in the
socket.
If the system has a belt printer, reconnect
P6.
Test Measuring Points Overvoltage Undervoltage
Voltage Tolerance Measured At
I
Reference
Sensei
Input
200 Vac, 60 Hz Ferro TB 1-2
Lower
Voltages
203 Vac, 60 Hz
±10% Ferro TB1-3
Ferro TB1-1
Limit
YAOO1
230 Vac, 60 Hz Ferro TB 1-4
200 Vac, 50 Hz
Ferro TB 1-2
"
220 Vac, 50 Hz
±10% Ferro TB 1-3
Ferro TB1-1
235 Vac, 50 Hz
Ferro TB 1-4
DC Power
Supply Voltages
Output -4 Vdc +4% -2%
PDTB2-4 PDTB1-l -4.18
Voltages
+5 Vdc
+10% -8% PDTB1-5 PDTB1-1 +5.5
-5 Vdc +10% -8% PDTB1-8
PDTB 1-1
-5.5
+6 Vdc +10% -8% PDTB2-3
PDTB 1-1
+6.6
+8.5 Vdc +10% -8%
PDTB2-1
PDTB1-1
+9.35
+12 Vdc +10% -8% PDTB2-5 PDTB1-l +13.2
-12 Vdc +10% -8% PDTB2-6 PDTB1-l -13.2
+24 Vdc
+10% -8%
PDTB2-8 PDTB1-l +26.4
-24 Vdc
+10% -8%
PDTB2-7 PDTB1-l
-26.4
Voltage Tolerance
Test Measuring Points
48 Vac
(serial printer)
Output
Dual Level
Min Nom Max
Voltage
48 Vac 41.5 46.5
51.15
Filter Assembly
E2.0 and E2.1
1
The over-voltage or undervoltage condition does not trip the power down sequence before the lower limit is reached, but
trips before the upper limit.
Sensei
Upper Lower Upper
Limit Limit Limit
-6.0
-3.88
-3.0
+6.1
+4.65
+3.8
-6.1
-4.7 -4.0
+7.6
+5.64 +4.6
+10.5 +7.99 +6.5
+16.0 +11.28 +9.2
-16.0
-11.28
-9.2
+29.25 +22.10 +18.25
-30.0
-22.56
-18.25