. A complete Parts List is available at www.MillerWelds.com

6-2. Fuse F1

Tools Needed:

3/8 in

YTurn Off power before open- ing rear access door.

 

1 Fuse F1 (See Parts List For

1

Rating)

 

Fuse F1 protects control transform- er from overload. If F1 opens, weld output and fan motor stops. Re- place F1.

Close and secure access door.

Ref. ST-800 101-C

6-3. Troubleshooting

Trouble

Remedy

 

 

No weld output; unit completely inop-

Place line disconnect switch in On position (see Section 4-14).

erative.

 

 

 

 

Check fuse F1, and replace if necessary (see Section 6-2).

 

 

 

Check and replace line fuse(s), if necessary, or reset circuit breaker (see Section 4-14).

 

 

 

Check for proper input power connections (see Section 4-14).

 

 

 

Check for proper jumper link position (see Section 4-13).

 

 

No weld output; Power switch pilot light

If using remote control, place Output (Contactor) switch in Remote 14 position, and connect remote

on; fan on.

control (see Section 4-11). If remote is not being used, place switch in On position.

 

 

 

Check, repair, or replace remote control.

 

 

 

Unit overheated. Allow unit to cool with fan On (see Section 4-2).

 

 

 

Have Factory Authorized Service Agent check control board PC1.

 

 

No weld output; Power switch pilot light

Check for proper input power connections (see Section 4-14).

on; fan off.

 

 

 

 

Check and replace line fuse(s), if necessary, or reset circuit breaker (see Section 4-14).

 

 

 

Have Factory Authorized Service Agent check SCR’s.

 

 

Unit provides only maximum or mini-

Have Factory Authorized Service Agent check control board PC1 and hall device HD1.

mum weld output.

 

 

 

Erratic or improper weld output.

Use proper size and type of weld cable (see Section 4-8).

 

 

 

Clean and tighten all weld connections.

 

 

 

Check position of Polarity selector switch (see Section 5-1).

 

 

 

Have Factory Authorized Service Agent check control board PC1 and hall device HD1.

 

 

No 115 volts ac output at duplex recep-

Reset supplementary protector CB1 (see Section 4-7).

tacle, Remote 14 receptacle.

 

 

 

No 24 volts ac output at Remote 14 re-

Reset supplementary protector CB2 (see Section 4-7).

ceptacle.

 

 

 

Fan not operating. NOTE: fan only

Check for and remove anything blocking fan movement.

runs when cooling is necessary.

 

 

 

 

Have Factory Authorized Service Agent check fan motor.

 

 

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Miller Electric 852 manual Fuse F1, Troubleshooting, Trouble Remedy