Chroma 6404 - Page 36

Programmable AC Source 6404/6408 User’s Manual
5-2
Problem
Reason
Solution
Poor Voltage
Accuracy
HIGH or LOW line of output
voltage maybe shorted to the
case ground.
Isolate output line from case.
Poor measurement of
V, I, P
Aging of components results in
deviation of characteristics.
Periodical calibration or
adjustment is required.
Refer to service manual for
internal reference of voltage
adjustment.
Over Temperature
Protection (OTP)
Ambient temperature is too high
Operate the unit between 0
and 40°C.
Over Load Protection
(OLP)
The output is overloaded.
Remove the overload.
Short Circuit (SHT)
The output is shorted.
Remove the short.
Over Power
protection (OPP)
The output power is over
specification.
Remove the over power or
lower down output voltage.
Cannot Control AC
Source System by
GPIB
1. The AC source unit address
is incorrect.
2. GPIB cable is loosened at
AC source rear panel.
1. Update address.
2. Check connection, tighten
the screws.
Distorted Output
1. The AC source output
voltage is too low.
2. The rectified load is too large
at high frequency.
1. Program higher output
voltage.
2. Reduce the load or lower
the output frequency.
Fan Inhibited
Protection (FAN)
Fan or ventilation holes are
blocked.
Remove obstruction.
Under Voltage
Protection (UVP)
The AC source line input voltage
is too low.
Measure input voltage, and
raise it if it is under the
specification.