AmeriWater SILEX 00M20821, Руководство по эксплуатации и техническому обслуживанию, Страница: 10 / 25

8
Using the Resistivity Relay
The resistivity controller has an on-board single pole, double throw relay that is
rated at 1 amp @ 28VDC and 0.5 amp at 120VAC. This has both normally open
and normally closed contacts, allowing for control both above and below the set-
points.
The relay acts simply as a switch. When the water quality is above the set-point
(Green LED), the relay is in a de-energized state and there is a completed circuit
between the COM and NC terminals of the relay. If the water quality is below the
set-point (Red LED), the relay is energized completing the circuit between the
COM and NO terminals, while simultaneously disconnecting the COM / NC
circuit. FIGURE 1 shows the connection location for the relay in the resistivity
controller.
Resistivity Meter Calibration
The resistivity meter should never require calibration. It is recommended to
verify the accuracy of the resistivity meter annually by comparing the value
shown on the meter against a sample from the post filter sample port and
analyzing this with a known good hand meter. In the event that the reading
cannot be verified within 5% accuracy, calibration can be performed as follows.
1. Power down the device and remove the line cord from the power source.
2. Open the access door to the electrical enclosure and remove the 4 screws
on the rear of the resistivity meter.
3. Remove the cover and locate the calibration trimmer (FIGURE 2), CAL /
R16, on the lower edge of the circuit board.
4. Locate TB1 and the 5 cell wires leading to positions 7-11.
5. Loosen the screws and disconnect the 5 cell wires.
FIGURE 1