Bunn U3 服务手册
Page 15
J2
SET
L
OC
K
LO
CK
SE
T
TL
1
TL
2
TL
3
TL
4
TL
5
J1
P09.60
FIG. 4 CONTACTOR
CONTACTOR
Location:
The contactor is located on the left front of the
component bracket
Test Procedures:
1. Disconnect the brewer from the power source.
A. 10/08V, 10/40V, 380V THREE WIRE MODELS,
380V and 440V FOUR WIRE MODELS
Disconnect the black wire from the contactor coil
to the limit thermostat and black wire from the
white wire on the main harness.
B. 08V or 40V TWO WIRE MODELS (Prior to
# U300004095), 08V and 40V THREE WIRE
MODELS
Disconnect the black wire from the contactor coil
to the limit thermostat and black wire from the red
wire on the main harness.
C. 30V MODELS (S/N U300004095 - UP)
Disconnect the red wire from contactor coil to the
limit thermostat and the black wire from the main
harness.
3. Connect the brewer to the power source.
4. Check the voltage across the coil wire and the wire
from the the main harness.The indication must
be:
SERVICE (cont.)
a) 10 volts ac for three wire 10/08, 10/40
volt and 380 volt models.
b) 30 volts ac for two wire 30 volt models.
c) 08 or 40 volts ac for two wire 08 or 40 volt
models.
d) 0 or 54 volts ac for four wire 80 or 440
volt models.
5. Disconnect the brewer from the power source.
If voltage is present as described, proceed to #6.
If voltage is not present as described refer to the Wiring
Diagrams and check the brewer wiring harness.
6. Check for continuity between the black leads on
the contactor coil or the left and right terminals
on the contactor coil on 30V models.
If continuity is present as described, reconnect the
wires and proceed to #7.
If continuity is not present as described, replace the
contactor.
7. On all brewers, with a voltmeter, check the voltage
across the upper left terminal and the upper right
terminal on the contactor. Connect the brewer to
the power source. The indication must be:
a) 10 volts ac for three wire 10/08, 10/40
volt and 380 volt models.
b) 30 volts ac for two wire 30 volt models.
c) 08 or 40 volts ac for two wire 08 or 40 volt
models.
d) 0 or 54 volts ac for four wire 80 or 440
volt models.
8. Disconnect the brewer from the power source.
If voltage is present as described, proceed to #9.
If voltage is not present as described, refer to the Wiring
Diagrams and check the brewer wiring harness.
10060 080900