Measurement Of The Internal Voltage Supply - Hitachi L100 SERIES Service Manual

2. Measurement of the Internal Voltage Supply

There are PV5L, PV24L and NV12L internal DC voltage supplies. These supplies are isolated from the
main high voltage portion. And it is not possible to measure DC voltages at the non isolated portion.
Please make measurements for above mentioned voltages for the isolated portion.
Check pad of NV12
1 pin of TM2 is "L"common
PV5L supply voltage
Supplies 5V for I/O board.
Nominal voltage : min. 4.90Vdc to max. 5.20Vdc
Check PV5(address 1C) <- L
PV24L supply voltage
Supplies 24V to interface voltage supply, which is supplied to input terminals.
Nominal voltage : min. 21.60Vdc to max. 26.40Vdc
Check PV24(address 1A) <- L
NV12L supply voltage
Supplies -12Vdc to remote operator (DOP/DRW's yellow backlight).
Nominal voltage : max. -10.80Vdc to min. -17.5Vdc
Check NV12(address 3A) <- L
"H" terminal voltage
Suppiles 10V to "H" terminal
Nominal voltage : min 9.5Vdc to max 11.5Vdc
Check "H" "L" with VR (1kohm)
<->
"Potentiometer function on the front case
Set "A01" :"00"
Monitor "F01" display 0
Cooling FAN voltage (PV24N)
Supplies 24V to cooling FAN .
Nominal voltage min 19.9Vdc to max 27.2Vdc.
Check Red wire
<-
Check the FAN working, check the air direction (from down to top)
50(60) with clockwise and anti clockwise.
<->
Black wire with the FAN.
Check pad of PV24
Check pad of PV5
2-1/E