14
• If the reading lies outside this range,
adjust the slope adjustment trimmer
on the transmitter for a reading just
within this range.
The unit is now calibrated.
A complete calibration of the transmitter
module is advised periodically.
This calibration procedure requires the
HI 8427
or the
HI 931001
pH
and ORP simulator to simulate the ORP electrode.
HI 8427
or
HI 931001
produce a known signal into the system so
that the faults of the system can be isolated.
• Connect the ORP transmitter to the simulator.
• Set the simulator to 0 mV and adjust the offset trimmer to read
12 mA on the ammeter or 0 mV on the
HI 8615L
display.
• Set the simulator to 350 mV and adjust the slope trimmer to
read 14.8 mA for
HI 8615
on the ammeter or 350 mV on the
HI 8615L
display.