48
APPENDIX 4. TROUBLESHOOTING – COMMON OPERATIONAL ERRORS
Problem
Possible Cause
Solution
Manual Page
Can’t Enable
High-voltage
Interlock is not
connected.
LED above ALL on front
panel will glow Red
when interlock is not
satisfied.
Connect interlock (50 Ohm terminator) to
back panel.
Twist interlock to get a good connection.
LED above ALL will glow Green when an
electrical connection is achieved.
pp.8, 14
Wrong HVS model
selected
View>Options>HVS448 Model> select
correct model
.
HVS not connected to
computer
See can’t communicate with computer
(below).
pp.8
,
9
Can’t
communicate
with
computer
RS232 cable not
connected
Verify RS232 cable securely connected to
HVS448 and computer.
If using a RS232 to USB adapter ensure the
adapter driver software is loaded on
computer.
pp.8
Wrong COM port
selected
Go to
View>Options>Communication…
and
select correct COM port.
p.9
Noisy
Channels
Operating at low
voltages (<200 V)
The HVS is designed for optimal
performance at high voltages.
Use a higher common-mode voltage to
achieve the desired potential difference (i.e.,
apply 1000 V to A and 900 V to B for 100 V
differential)
If you must operate at low voltage reference
to the case ground, the output can be
stabilized by loading the channel with an
external resistor, either to ground or
preferable to a voltage applied by another
channel so that several 10s of microamps
flow from the channel. Make sure the
resistor can take the applied power and that
the resistor does not overload the channel.
p.7
No voltage
applied
High-voltage is disabled
Toggle
Enable High Voltage
button on
toolbar.
p.8
Incorrect
voltage
applied
Active voltage control is
not selected
Go to
View>Options
. Ensure
Active Voltage
Control
is checked.
p.42
Out of range
voltage error
Voltage set outside
range
In the
Manual High-Voltage Power Supply
Controls
window, ensure set voltages for
each channel are consistent with “Output
voltage range” selection.
p.20
