Step
Settings
1.
O/P off
2.
0V
3.
Max V, 1A
4.
Max V, 1A
5.
Max V, 1A
6.
I
pot at 0
7.
4V, 0A
8.
4V, 0A
9.
4V, 10A
10.
4V, 10A
11.
O/P off
Powerflex Adjustment
This is factory set and would not normally need to be readjusted during routine calibration.
However, if a component in that part of the circuit has been changed, proceed as follows. These
adjustments are on the Control PCB mounted behind the front panel, accessed by removing the
top cover which is secured by 6 screws.
When the instrument is connected to its supply the removal of covers is likely to expose live parts.
Any adjustment of the opened instrument under voltage shall be avoided as far as possible and, if
inevitable, shall be carried out only by a skilled person who is aware of the hazard involved. Note
in particular that the heatsinks and other components to the rear of the fan are at a hazardous
voltage.
VR1/VR2 are the PowerFlex adjustments; these potentiometers can be found close to the current
shunt heatsink. VR1 is accessed from above and VR2 from the side
Set the PSU to maximum volts and current.
Set the load to 7.35A and switch on.
Adjust VR1 so that the UNREG led just comes on.
Set psu voltage to 22V.
Set the load to 20.00A.
Adjust VR2 for 21.1X volts (UNREG led should be on).
These adjustments are most easily performed using an electronic load.
36
Display
Adjust for
−5mV ± 2mV
Cal count
Cal count
0V ± 2mV
Cal count
60V ±2mV
O/P volts
Display = DVM
OVP setting
Display = DVM
Display = 0
I
pot
Cal count
0mA ± 2mA
O/P amps
Display = milli-ammeter ±2mA
Change load
Cal count
10A ±10mA
O/P amps
Display = ammeter
End
-
WARNING!
Load
Detail
DVM
O/P off volts
DVM
V
DAC zero
DVM
V
DAC scale
DVM
V
metering scale
DVM
OVP
-
I
pot ADC zero
milli-ammeter
I
DAC zero
milli-ammeter
I
metering zero
Ammeter
I
DAC scale
Ammeter
I
metering scale
-
Stores and exits