28 english, Maintenance procedures – Robinair 17801B Recovery, Recycling, Recharging Unit User Manual
Page 30
© Bosch Automotive Service Solutions LLC
28
ENGLISH
12. To check scale accuracy, follow the Correct Weight Verification procedure.
WARNING
Unplug the unit before beginning service work. Incorrect use or
connections can cause electrical shock. Only qualified personnel
should perform service work.
If scale assembly and UL circuit are not calibrated, scale can overfill
the tank, causing possible explosion and/or vehicle overcharge.
UL CIRCUIT CALIBRATION
NOTE: Always calibrate the scale first. Then remove the (4) screws that hold down
the keypad on the control panel before attempting to calibrate the UL circuit.
1. Remove all weight from the scale platform.
2. Turn on the
MAIN POWER.
NOTE: If the unit is just being turned on, the screen will default to display the
selected refrigerant type.
3. Press
SHIFT/RESET until “PROGRAM” displays.
4. When the “PROGRAM” message displays, press
SHIFT/RESET and ENTER
at the same time. The “FUNC” message displays.
5. Press
6.
NOTE: Any weight on the scale when 6 is pressed will not be shown on the display.
The unit automatically zeros the weight on the scale when
6 is pressed. If you re-
move the weight, the display will show the change in total weight, but will not show
a negative sign.
6. Place a known weight of EXACTLY 75 lbs. on the scale platform. The dis-
play will show “75 lb. ± .04 lbs/.02kg.”
7. Adjust the potentiometer (P1 POT) set screw just until the “HOLD” message
displays. (The potentiometer adjusting screw is located on the circuit board.)
Maintenance Procedures
NOTE:
You must have
a known weight
of 75 lb. ± .01
(34.02 kg ±.005).