Bunn FPG-2 ユーザーズマニュアル

37

P2946

FIG 34 POTENTIOMETERS

Location:

 

The potentiometer switches are located on the top 

rear of the hopper housing.

Test Procedure:

1.  Disconnect the grinder from the power source.

2.  Open hopper lid and loosen four screws inside the 

hopper and remove hopper.

3.  Disconnect the BRN wire from the control board.

4.  Disconnect the PNK, GRY, and TAN wires from the 

front selector switch.

5.  Connect an ohmmeter to the BRN wire. Connect 

the other lead from the meter to the TAN wire. 

Turn the knob for the SMALL potentiometer all the 

way counterclockwise. The meter should read <3K 

ohm. Turn the knob all the way clockwise, the meter 

should read between 94K and 116K ohms.

6.  Connect an ohmmeter to the GRY wire. Connect 

the other lead from the meter to the TAN wire. 

Turn the knob for the MEDIUM potentiometer all 

the way counterclockwise. The meter should read 

<3K ohm. Turn the knob all the way clockwise, the 

meter should read between 94K and 116K ohms.

7.  Connect an ohmmeter to the TAN wire. Connect 

the other lead from the meter to the TAN wire. Turn 

the knob for the LARGE potentiometer all the way 

counterclockwise. The meter should read between 

13.5K and 19.5K ohms. Turn the knob all the way 

clockwise, the meter should read between 108K 

and 132K ohms.

FIG 35 POTENTIOMETER TERMINALS

BRN to BRN WIRE 

at TIMER

PNK to BATCH SELECTOR SWITCH

GRY to BATCH SELECTOR SWITCH

TAN to BATCH SELECTOR SWITCH

If continuity is present at all positions, the potentiometer 

switches are operating properly.

If continuity is not present at any position, replace the 

potentiometer switches.

8.  Refer to Fig 35 when reconnecting wires.

Removal and Replacement:

1.   Disconnect the grinder from the power source. 

2.  Remove the four 8-32 screws attaching the rear 

access panel and move aside.

3.  Disconnect three wires to the batch selector switch 

and the one wire to the timer.

4.  Loosen the setscrews on the switch knobs and 

remove the knobs.

5.  Remove the three nuts and lockwashers attaching 

the switches to the rear access panel.

6.  Inspect and replace the adhesive backed sponge 

washers on the rear access panel if necessary.

7.  Install the new potentiometer switches and tighten 

the lockwashers and nuts.

8.  Replace the knobs and tighten the setscrews.

9.Refer to Fig. 35 when reconnecting wires.

41545 122209