Det-Tronics R8471J Single Channel Gas Controller, OPECL - Manual (Page 13)

1.1 95-8572 11
Zero calIBratInG oPecl
To zero calibrate the OPECL unit, follow the calibration
procedure described in the OPECL instruction manual
(95-8556).
NOTE
For best calibration results, allow the OPECL
detector to operate for at least two hours to
ensure a stable output before performing zero
calibration.
calIBratInG tHe controller
Factory Default calibration
Perform the following procedure to set the R8471J
Controller to the factory default calibration values.
1. Press and hold the Reset button for approximately
9 seconds until the digital display begins flashing
and the CAL LED is illuminated. Release the Reset
button.
2. Press the Set button. The FAULT LED comes on.
3. Press the Reset button. The controller returns to the
normal operating mode (after a short time delay).
4. The controller is now set for the factory default
values.
cUrrent oUtPUt calIBratIon
The controller’s 4 to 20 milliampere output is calibrated
at the factory, however, it can be recalibrated by
performing the following procedure.
1. A dc current meter capable of measuring 4 to 20
milliamperes must be connected to the current loop
output. This can be accomplished in one of the
following ways:
— by disconnecting all loads and connecting a dc
ammeter between the two 4 to 20 milliampere
terminals,
— by connecting a dc ammeter in series with the
load,
— by connecting a digital dc voltmeter across
a known load resistance and calculating the
current flow using the formula:
I = voltage/load resistance.
2. Press and hold the Set button, then immediately
press the Reset button. (The Reset button must
be pressed within one second of pressing the Set
button.) Release both buttons. The Low LED should
flash slowly. The flashing Low LED indicates that
the system is now generating a 4 mA output.
3. Press the Reset (increase) or Set (decrease) button
to obtain a 4 mA reading on the meter. (Pressing
and holding the button will cause the output to
change rapidly.)
4. When no adjustments have been made for 7
seconds, the controller automatically switches to a
20 mA output. This is indicated by a flashing High
LED. Press the appropriate button to obtain a 20
mA reading.
5. When no adjustments have been made for 7
seconds, the controller generates the current output
level for the calibrate mode. This is indicated by a
flashing CAL LED. Press the appropriate button
to obtain the desired current output level for the
calibrate mode.
6. When no changes have been made for 7 seconds,
the controller automatically returns to the Normal
operating mode and saves the data in non-volatile
memory.
7. Remove the meter from the system output.