KERN HFC, Service Manual

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HFC-SH-e-1510 35
11.4 Testing PCB Voltages
If the problem is in the PCB, use a multimeter to check the following voltages
AC Power
Check the AC power socket out put voltage.

Voltage must be a -20% and +10% of the normal AC voltage.
adapter Voltage
Check the adapter output cable connecter voltage

Voltage must be minimum 9VDC and maximum 12VDC
PCB Input Voltage
Check the PCB input power connecter voltage

Voltage must be minimum 9VDC in to the pin AD+
Check Battery Voltage and Charging Voltage
1. Check the Battery Voltage,

Voltage must be minimum 6VDC. If below the 6VDC connect the adapter for
charging

The battery voltage below the 5.5VDC, replace the battery and install new
battery.
2. Check the Battery Charging Voltage;

Remove the battery connection terminals (Red and Black) from the battery.

Connect the power and turn on the scale

Voltage into the terminal minimum 6.5VDC
11.5 Trouble Shooting
Problem
Possible Cause Common Solutions
Display is blank, no self-
checking Mains power is turned off.
Power supply not plugged in
Internal battery not charged
Display turned off Check the power is
going inside and switch
is turned on. Verify the
voltage
After self-checking error
message stuck Crane not installed
Unstable weight
Load cell damaged
Mechanics damaged Check again after turn
on the scale
Check the load cell
connecters
OL or ------ appears on
the display Maximum capacity
exceeded
Load cell or mechanism
damaged
Power supply fault Check the crane is
installed correctly
Check again after turn
on the scale
Check the power
connecters