Tektronix Waveform Monitors WFM700 Series User Manual
Page 18
Functional Overview
WFM700 Series Waveform Monitors User Manual
2- 3
Table 2- 2: LED fault codes
State
ON/STBY
LED
Fault LED
Main power
relay
Description / suggested action
Standby
Off
Off
Off
No power. Press the ON/STBY switch for normal operation. Check
that the instrument power cord is plugged into the local power supply.
On
On
Off
On
Normal operation.
Cold
Flashing
Off
On
The LCD may be damaged if operated at low temperatures. If the
internal temperature sensors detect a low temperature, this fault code
will be asserted. Let the unit warm up and cycle the power or press
the ON/STBY switch for normal operation to occur.
Momentary
fault
On
On
On
This is a transient state. It should never last more than one second. It
occurs when the internal sensors detect that one of the internal
supplies is out of the allowable range. In this state, the instrument will
be reset.
This state can occur due to an intermittent problem that requires
service or from a drop-out on the AC line. If the fault persists for more
than one second, then the instrument will go to the Power Supply
Fault state.
It is normal for the momentary fault state to be asserted when the AC
line is removed while the instrument is running.
Power supply
fault
Off
On
Off
If the internal monitors detect that one of the internal power supplies is
out of its allowed range, the instrument will shut down and the Power
Fault LED code will be asserted. This can be triggered by multiple
drop-outs on the AC power supply to the instrument.
If this fault code is present, press the ON/STBY switch to reset the
instrument. If the fault code reoccurs, refer the instrument to qualified
service personnel. If the waveform monitor seems to be operating
properly, monitor the AC power supply to be sure there are no
problems in the power source.
Overtemp
fault
Off
Flashing
Off
The internal temperature sensors will shut down the instrument at
75
_C to prevent damage to the components if the ambient
temperature is too high or if the airflow is blocked.
If this occurs, the Overtemp fault code will be asserted. Let the
instrument cool down and cycle the power or press the ON/STBY
switch to resume normal operation.
EC self test
failed
Flashing
Flashing
Off
This is asserted if the Environmental Controller is not able to test the
temperature sensors and fan circuits. If this occurs, refer the
instrument to qualified service personnel.