Proximity Sensor - Bunn Fast Cup Series Service & Repair Manual

LOWER FRONT PANEL

Proximity Sensor

Purpose: The proximity sensor is used to validate
"Home" position for the upper piston assembly be-
fore start of a brew process.
The sensor is mounted to the underside of the piston
motor top bracket. A metal locator post is secured
on top of the upper piston/latch assembly. When the
metal post is aligned by the side of the proximity
sensor, it is referred as "At Home" position and metal
post away from the sensor is referred as "Not Home"
position.
TEST INSTRUCTION
Enter Service Technician Mode and Select
Service icon
Factory Locator Post Height Specification: In the
event of "Home" position error or related service to
the upper piston, check the Locator Post for correct
height setting of 1.0 inch.
The dimension specification is taken from the top of
the locator post to the top of the sensor mounting
plate. See Fig. 1.
Step 1: Select and enter the Brew Module tab. The
Brew Piston buttons on the right of the
display will move the piston to designated
mm position point when touched.
Step 2: Door switches must be enabled or in
service On position to test operation.
Step 3: Touch a Brew Piston position point button
to move piston from At Home to Not Home
position. The reading is displayed in the
lower right corner of the test screen.
Step 4: Next, touch the Brew Piston Home button.
Piston will move back home and read At
Home in the lower right corner of the
test screen.
Step 5: No change in position reading - Verify
proximity switch for voltage before
replacing sensor.
SERVICE
Proximity Sensor
&
Locator Post
Locator Post
1.0 inch
Fig. 1
1
49
Sensor Plate
Proximity Sensor
At Home
4
Not Home
3
Continued >
4
3
4