Fetco GR Series User Manual - page 4
4
Principles of Operation
GR-1
When one of the start switches is pressed, the timer energizes the grinding motor. The coffee beans are fed into
the grinding chamber by a rotating auger spring. When the timed cycle is complete, voltage is removed from
grinding motor.
The power/stop switch is used only when it is necessary to interrupt the grind cycle before the cycle is finished.
GR-2
When one of the start switches is pressed, the timer simultaneously energizes the grinding motor and the hopper
solenoid. The hopper solenoid opens the guillotine on the bottom of the hopper, which allows the coffee beans to
drop into the grinder. The coffee beans are fed into the grinding chamber by a rotating auger spring.
When the timed cycle is complete, voltage is removed from the hopper solenoid and the guillotine closes, stopping
the flow of beans out of the hopper. The auger spring continues to feed any remaining beans into the grinding
chamber.
Several seconds after the guillotine closes, voltage is removed from the grinding motor. This delay ensures that all
beans have passed through the grinding chamber, preventing cross contamination of different coffees.
The motor delay is factory set at 8 seconds, but can be adjusted if necessary. (See Programming section.)
The power/stop switch is used only when it is necessary to interrupt the grind cycle before the cycle is finished.
Grinder Foreign Object Protection
FETCO coffee grinders feature two types of overload protection to prevent damage to the unit if a foreign object
enters the grinding chamber and stalls the motor.
• The control board is equipped with a thermal breaker with an audible alarm that will cut power to the motor
if the control board overheats.
• The motor is equipped with a thermal breaker (no alarm) that will cut power to the motor if the motor
overheats.
Once the foreign object is removed and the unit cools down, the thermal breakers will automatically reset.
Warning: If this occurs D
O NOT TRY TO FIX THIS PROBLEM YOURSELF
. Immediately unplug the grinder and call a
qualified service technician.
Grind Adjustment
1. Empty the hopper(s).
GR-1: Scoop out as many beans as possible. Lift the window up and sweep out the remaining beans.
GR-2: Remove both hoppers and dump the beans out. Place both hoppers back in grinder.
2. Press one of the large portion switches. This will clear the grinding chamber of any remaining beans.
3. Remove the front cover. There are 2 screws in front and 2 underneath near the coffee outlet.
4. Using a 7/8” or 22 mm wrench turn the retaining nut counter-clockwise at least one turn.
5. Using a 3/8” to 1/2” standard screwdriver turn the adjustment screw clockwise for a finer grind, counter-
clockwise for a coarser grind.
Note: Do not exceed more than a 1/4 turn in either direction.
6. Turn retaining nut clockwise, locking adjustment screw in place.
7. Grind a small amount of coffee beans to test the setting. Repeat the above steps if necessary.
To reset the grind setting to the factory default:
• Follow steps 1 - 4 of the grind adjustment procedure.
• Turn the adjustment screw clockwise until the grinding discs touch, then
back off slightly.
• Using a marker, mark the twelve o’clock position of the adjustment screw.
• Turn the screw counter clockwise to just past the four o’clock position.
• Turn retaining nut clockwise locking adjustment screw in place.
• Test by grinding a small batch.
Note: It may be necessary to adjust the grind time to compensate for the new grind setting.
A finer grind will produce less ground coffee per minute and a coarser grind will produce more ground coffee per minute.
FINE
COARSE