O'\
I w
Problem
l.
Power light wi II not light (all
functions inoperative.)
Refer to Fig. 5 -3.
6.3 Input Power Problems
Possible Cause
I.
Power cord not plugged in.
2.
No power to receptacle.
3.
Controller fuse FI blown.
4: Defective transformer T4.
Check for continuity of primary winding.
Switch S5 defective.
"'))
Cure
Plug in power cord.
Restore power to receptacle.
Replace fuse with correct type and
value; l-l/4A slo blo for l00V
operation, and 115V operation,
l /2A slo blo for 230V operation.
Replace T4 if defective.
Replace S5.
2.
Controller power fuse Fl blows as
soon as the power switch is turned
on. Refer to Fig. 5-3.
I.
Incorrect power source. Check
power source vs. controller requirements.
Connect con tro Iler to proper source
of power or reset selector switching
as shown in Fig. 4-2.
2.
Incorrect fuse rating.
3.
Defective component of power supply
P.C. board. Remove gauge cable,
interconnect cable to main board and
thermocouple gauge cable. If problem
remains, trouble is with T4, CR26, C 19,
C20, C27, C2 I.
Use correct fuse. A 1-1 /4 or I .25A
"slo blo" for I 00V operation and 115V
operation, I /2A "slo blo" for 230V
operation.
Locate defective component and
replace.
6.4 Power Supply Problems (Refer to Fig. 5-3 and Fig. 6-2)
Whenever a problem persists after elimination of possible external
causes by removing all cables but the power cable, and thus appears
to be in the controller, the power supplies should be checked first.
Use a standard DVM to check the labeled points on Fig. 6-1 and 6-2
for the fol lowing outputs with respect to ground:
