RLE GD100 - Manual (Page 19)

CTS-M17 Installation, Operation and Maintenance Manual
B84450-001-000 RG May 12, 2005 18
Apply zero gas (clean air) adjust the ZERO (VRES1) potentiometer until the display
reading is 00.0. (Remember that the 4-20 mA signal may be set to a different
range.)
Apply an appropriate span gas (e.g. 2.5% CH4 = 50% LEL CH4), and adjust the
GAIN (VRES2) potentiometer to get the correct reading on the display.
Note: If the Auto-zero is enabled, you must perform the AUTOZERO | Clear
function to reset the Auto-zero history in memory.
2.4.3 Calibration Errors
If the gas flow was not sufficient, or the bayonet adapter was too loosely applied,
the gas concentration in the sensor will stabilize at an incorrect low value. Repeat
the calibration procedure if you suspect an incorrect calibration.
3. Faults
3.1 Self-check Faults
The microprocessor monitors a number of operational values for faults, and will
display each occurrence for two seconds as follows:
F F A A U U L L T T
X X X X X X
Where XXX is a fault code.
The unit will automatically restart and continue normal operation if the fault
occurred due to a temporary intrusion (e.g.: Radio frequency interference or water
condensation formed due to fast temperature change).
A fault shown repeatedly indicates malfunction of the unit. In such cases the fault
code should be recorded and the unit returned for repair.
When a fault is detected, the output is dropped to 0.0 mA and both relays are
deactivated.
The only Self Check Faults which can be field addressed are those which refer to
problems with the sensor (fault codes 040 through 042 for sensor faults, and 048
through 050 for calibration faults):
• Check that the sensor is installed in the sensor socket correctly.
• Replace sensor. If the fault is removed, then re-calibrate.
• Return unit to Factory.
Note: To calibrate the unit, it may be necessary enter the menu system
while the unit is cycling through a fault display, trying to recover
normal operation. To enter the menu system in this state,
immediately press any key and hold after hearing the turn-on beep,