PART THREE - OPERATION
SECTION 1 - OPERATING CONTROLS
Rev. 9-898
Model 692P
-23-
this prevents a pump or valve from operating, therefore
conserving use of costly chemicals. For example, the
process may typically be controlled between 7 and 8 pH
with a tendency to increase without chemical addition. If
an out-of-range condition occurs in this example, you
can be prevent unwanted chemical addition by preset-
ting the Model 692 for a low out-of-range default state.
This causes the display to indicate 0 pH and provides
the corresponding loop current (4 or 20 mA).
0 pH POSITION (on/left) - Selects the low out-of-range
state default. When the 692 detects a defective pH sen-
sor or shorted sensor cable, the display indicates 0 pH
with an “ERR 1” or “ERR 3” diagnostic message, and the
692 provides a corresponding loop current (4 or 20 mA).
14 pH POSITION (off/right) - Selects the high out-of-range
state default. When the 692 detects a defective pH sensor
or shorted sensor cable, the display indicates 14 pH with
an “ERR 1” or “ERR 3” diagnostic message, and the unit
provides a corresponding loop current (4 or 20 mA).
11.
SWITCH 3
(Figure 3-2)
COMB. POSITION (on/left) - Sets the 692 for use with a
combination electrode.
DIFF. POSITION (off/right) - Sets the 692 for use with a
GLI 5-wire Differential Technique sensor.
12.
SWITCH 4
(Figure 3-2)
°
F POSITION (on/left) - Selects measured temperature
to be displayed in
°
F.
°
C POSITION (off/right) - Selects measured tempera-
ture to be displayed in
°
C.
13.
TEMP. COMP.
switch (Figure 3-2)
RTD - Sets the 692 for use with a 1000 ohm RTD
temperature sensor for automatic temperature compen-
sation.
THERM. - Sets the 692 for use with a 300 ohm ther-
mistor temperature sensor for automatic temperature
compensation (or a specific-valued resistor for fixed
temperature compensation).
