14
MODEL 5081-A
SECTION 3.0
SENSOR WIRING
FIGURE 3-3. Free chlorine sensor with
standard cable and 399vP-09 pH sensor without
internal preamplifier.
FIGURE 3-4. Free chlorine sensor with standard cable
and 399-14 pH sensor with internal preamplifier.
If the preamplifier is in the sensor, a default setting in the
transmitter must be changed. See Section 7.8.3.
Free chlorine sensor cable
pH sensor
Figure
Standard
399VP-09
3-3
Standard
399-14
3-4
Standard
399-09-62
3-5
EMI/RFI or Variopol
399VP-09
3-6
EMI/RFI or Variopol
399-14
3-7
EMI/RFI or Variopol
399-09-62
3-8
3.2 WIRING MODEL 499ACL-01 (Free Chlorine) SENSORS AND pH SENSORS
If free chlorine is being measured and the pH of the liquid varies more than 0.2 pH unit, a continuous correction for pH
must
be applied to the chlorine reading. therefore, a pH sensor must be wired to the transmitter. this section gives wiring
diagrams for the pH sensors typically used.
When using the 499ACL-01 (free chlorine) sensor with a pH sensor, use the RTD in the pH sensor for measuring
temperature. DO NOT use the RTD in the chlorine sensor.
the pH sensor Rtd is needed for temperature measurement during buffer calibration. during normal operation, the Rtd
in the pH sensor provides the temperature measurement required for the free chlorine membrane permeability correction.
Refer to the table to select the appropriate wiring diagram. Most of the wiring diagrams require that two or more shield
wires be attached to a single terminal. use the pigtail wire and wire nuts provided with the chlorine sensor to make the
connection.
Insulate and tape back unused wires.
