84
Optional device installation
7.3.2 ORP probe programming
1.
From the Main Menu, select
OPTIONS, ADVANCED OPTIONS, DATALOG.
2.
Highlight Select Inputs using the
up
and
down
keys and press
SELECT
.
3.
Highlight ORP using the
up
and
down
keys, then press
SELECT
.
4.
Press
CHANGE CHOICE
to cycle between Logged and Not Logged, then press
ACCEPT
to continue.
5.
Enter a logging interval using the numeric keypad, then press
ACCEPT
. Valid logging
intervals are shown on the status bar along the bottom edge of the display.
6.
Select another channel to configure or press
RETURN
to back up one step or press
MAIN MENU
to return to the Main Menu.
7.3.3 ORP probe calibration
7.3.3.1 ORP preamplifier/junction box calibration
Calibration of the ORP input circuit requires a source of dc voltage between 500 and
2000 mV dc. The reference voltage must be applied to the ORP input terminals on the
preamplifier/junction box during calibration. A regulated dc power supply or a standard
“C” cell battery (1500 mV dc) make excellent sources for reference voltage.
1.
From the Main Menu, select
OPTIONS, ADVANCED OPTIONS, CALIBRATION, ORP.
2.
Install the ORP junction box on the sampler with the ORP probe removed.
3.
Apply a positive reference voltage to the ORP probe terminals in the junction box,
using either a 1.5 V dc “C” cell battery or a regulated power supply.
4.
Attach the positive battery terminal to the terminal block screw labeled “glass” and
the negative battery terminal to the terminal block screw labeled “ref.”
5.
After making all connections, measure the exact voltage on the “C” cell or power
supply with a voltmeter. Then press a key to continue. The sampler displays the
message “Waiting for ORP to Stabilize.”
6.
Once the reading is sufficiently stable enter a new millivolt level. The “C” cell battery
should be approximately 1500 mV (or 1.5 V) when new. Enter the exact voltage of
the current source in millivolts.
7.
Press
ACCEPT
to store the new calibration values.
8.
Disconnect the “C” cell battery or regulated power supply from the ORP input
terminals.
9.
Reconnect the ORP Probe leads to the input terminals.
Goodnal STP ST041 Pre Treatment (Sigma 900 MAX All Weather Refrigerated Sampler) Vendor Manual
Q-Pulse Id VM373
Active 29/10/2013
Page 84 of 122
