IBM 6580 User Manual

SECTION 8. POWER SUPPLY ISO-
LATION
1.
Us ing a ground indicator
multimeter, verify that
outlet is wired correctly.
or CSR
the AC
2. Verify the AC input voltage at the
wall outlet is in the following
specifications:
3.
4.
US/Canada
WT
WT
Verify
the
104 - 127 VAC
90 137 VAC
180 - 254 VAC
AC output
voltage
to
the diskette unit
at
connector
8
of
panel
2 is in
the above spec-
ification.
Verify all power
supply voltages
at
P1, P2,
and
10 are in the fol-
lowing
specifications: (See
Cables, Connectors, and
Points section of this manual
pin locations.)
+24VDC
+12VDC
+12VDC*
+ 8.5VDC
+ 5VDC
.. 5VDC
-12VDC
+22.08 to +26.4
+11.04 to +13.20
+11.40
to +12.60
+8.245 to +8.925
+4.6 to +5.5
-4.6 to -5,5
-11.04 to -13.20
the
Test
for
* (only connector P2, Pin 10)
5. Verify there are no DC or AC volt-
ages on any ground loop. Measure
between frame ground and signal
ground with the multimeter.
6.
7.
8.
Turn the system power off, and
measure for continuity (less than
2 Ohms) between frame ground and
all ground wires.
Run the BAT in a loop mode (RNA
Test G) while flexing (moving) all
cables going from the power
supply.
Run the system exerciser in a loop
mode while flexing (moving) all
cables going from the power
supply.
AC ripple on a DC supply may cause
intermittent failures. Check for
excessive AC ripple by using the 2
VAC scale and measure from frame
ground to the DC voltage point
being checked. If AC ripple
exceeds .2VAC the power supply
should be suspect.
Note: Excessive AC ripple may
not be present at all times.
Note: If you suspect another area,
see that section. If not, see Section
9.
Chapter 10. Intermittent Problem Diagnostic Approach 10-13

IBM 6580 Specifications

General

Brand	IBM
Model	6580
Category	Desktop
Language	English