Filter
Top Products
T400 Ozone Analyzer Operator’s Manual Troubleshooting & Service
261
12.7.4. TOUCHSCREEN INTERFACE
Verify the functioning of the touchscreen by observing the display when pressing a
touchscreen control button. Assuming that there are no wiring problems and that the DC
power supplies are operating properly, but pressing a control button on the display does
not change the display, any of the following may be the problem:
The touchscreen controller may be malfunctioning.
The internal USB bus may be malfunctioning.
You can verify this failure by logging on to the instrument using APICOM or a terminal
program. If the analyzer responds to remote commands and the display changes
accordingly, the touchscreen interface may be faulty.
12.7.5. LCD DISPLAY MODULE
Verify the functioning of the front panel display by observing it when power is applied
to the instrument. Assuming that there are no wiring problems and that the DC power
supplies are operating properly, the display screen should light and show the splash
screen and other indications of its state as the CPU goes through its initialization
process.
12.7.6. RELAY PCA
The Relay PCA can be most easily checked by observing the condition of the status
LEDs on the Relay PCA (see Section 12.3.2), and using the SIGNAL I/O subm
enu
under the DIAG menu (see Section 12.1.3) to toggle each LED ON or OFF.
If D1 on the
Relay PCA is flashing and the status indicator for the output in question
(Heater power, Valve Drive, etc.) toggles properly using the Signal I/O function, then
the associated control device on the Relay PCA is bad.
Several of the control devices are in sockets and can be easily replaced. The table below
lists the control device associated with a particular function.
Table 12-8: Relay PCA Control Devices
FUNCTION
CONTROL
DEVICE
IN SOCKET
UV Lamp Heater Q2 No
Optional IZS O
3
Gen Heater Q3 No
Optional Metal Wool
Scrubber
K1 Yes
All Valves U5 Yes
06870C DCN6332