13
SERVICE (cont.)
Timer
Location:
The timer is located on the timer bracket in the
grinder base. The bracket can be removed by loosen-
ing the two 8-32 screws beneath the timer dial(s).
Test Procedure:
1.
Disconnect the grinder from the power supply.
2.
Check the voltage across terminals TL1 & TL2
with a voltmeter when the “Off/On/Start switch
is placed in the “START” (right) position and re-
leased. Connect grinder to the power supply. The
indication must be:
(a) 120 volts ac for two wire 120 volt models.
(b) 240 volts ac for two wire 240 volt models.
3.
Disconnect the grinder from the power supply.
If voltage is present as described, proceed to
step 4.
If voltage is not present as described, refer to
the
Wiring Diagram and check the grinder wiring har-
ness.
4.
Remove the white/orange and white/yellow wires
from terminals TL3 & TL5.
5.
Check for continuity across the white/orange and
white/yellow wires when the Off/On/Start switch
is placed in the “START” (right) position.
If continuity is present as described, reconnect
the white/orange wire to terminal TL3 and the white/
yellow wire to terminal TL5, and proceed to step 6.
If continuity is not present as described, refer
to the
Wiring Diagram and check the grinder wiring
harness.
6.
Check the voltage across terminals TL1 and TL4
with a voltmeter when the Off/On/Start switch
is placed in the “START” (right) position and re-
leased. Connect grinder to the power supply. The
indication must be:
(a) 120 volts ac for two wire 120 volt models.
(b) 240 volts ac for two wire 240 volt models.
7.
Disconnect the grinder from the power supply.
If voltage is present as described, the timer is
operating properly. Refer to the
Adjustments section
to vary the amount dispensed.
If voltage is not present as described, replace
the timer.
Removal and Replacement:
1.
Remove all wires from the timer terminals.
2.
Remove the four 6-32 screws and nuts holding
the circuit board to the timer bracket.
3.
Remove the two 6-32 screws and nuts holding
the dial plate to the timer bracket.
4.
Install the new dial plate and circuit board to the
timer bracket.
5.
Refer to the illustration below when reconnect-
ing the wires.
6.
Refer to the
Adjustments section to vary the
amount dispensed.
MINUTES
BUNN-O-MATIC
P/N 2620- 120 VAC
MINU
TE
S
BUNN
-O-M
ATIC
P/N 2620- 120 VAC
2
3
4
5
WHI/RED to Relay N.O.
WHI/RED to
Off/On/Start Switch
WHI to Cordset (120 v)
RED/BLK to Cordset (240 v)
WHI/ORA to
Off/On/Start Switch
WHI/GRN to Relay Coil
WHI/YEL to
Off/On/Start Switch
P1312
P1313
Single set timer shown
Multi set timer (Urn/Carafe) connections are the same
Single set timer shown
Multi set timer (Urn/Carafe) similar
10171 121597