ONICON System-30 BTU - Manual (Page 20)

11451 Belcher Road South, Largo, FL 33773 • USA • Tel +1 (727) 447-6140 • Fax (727) 442-5699 • [email protected]
System-30 BTU Measurement System Manual 05/14 - 0667-2 / 18335
Page 20
4.2 COMMISSIONING
Please read all installation instructions carefully before proceeding. Wiring diagrams are located
in the appendix. A worksheet for checking off these steps and recording measured values is
located on the following page.
1. Confirm main unit location and
adequate straight pipe run to
achieve desired results.
Confirm orientation with respect
to flow.
Is the main unit located in the correct location as required by the
plans?
Is the meter correctly oriented with respect to flow direction?
Compare actual straight pipe upstream and downstream of the main
unit location to the recommended distances identified in this manual.
Note: This manual is very conservative and assumes the worst-case
pipe obstructions. Contact ONICON to discuss specifics of your
application.
In order to proceed with the following steps, the System-30 must be operating and connected to the control
system. There must also be flow in pipes. Flow signal readings should be taken while holding the flow rate
constant if possible; otherwise, take the various output readings as quickly as possible.
2.
Confirm correct supply voltage. Verify that the correct supply voltage is available at the System-30
signal cable connections. The System-30 BTU MEASUREMENT
SYSTEM operates from 24 VAC ± 4 volts.
3. With the HVAC system active,
verify that the diagnostic LED’s
for FLOW and BTU are both
flashing.
The LED’s are located on the exterior of the main unit on the end
opposite from the cables.
The following steps require a multi-meter with the ability to measure DC voltage as well as DC frequency in
hertz. Remove the six screws that secure the cover to the main unit and carefully lift the cover off.
4.
Check temperature readings for
T1, T2 and the differential
temperature.
Set multi-meter for 2 to 4 volt range.
T1: (TB2) Measure DC volts between terminals 2(+) and 3(-).
T2: (TB3) Measure DC volts between terminals 2(+) and 3(-).
Delta T: (TB2-TB3) Measure DC volts between terminals 2 and 2.
The relationship between voltage and temperature is 10 mV/degree F.
Multiply the reading in volts by 100 to obtain degrees F. Compare the
calculated temperatures to expected values.
5. Check flow signal. Set multi-meter for DC hertz, voltage range > 15 volts. The test points
for flow are located next to the reset button.
GPM = Frequency in Hz X 60
Meter Factor in ppg (refer to calibration tag for meter factor)
Compare the calculated flow rate to expected values.
6. Check Energy Total Output (BTU
Output Mode 1 and/or Mode 2).
Set multi-meter for DC volts, voltage range > 15 volts.
Mode 1: Measure DC volts between terminals 3 and 4
Mode 2: Measure DC volts between terminals 5 and 6
Confirm that the voltage changes state (low to high or high to low)
each time the controls system register records a new energy total.
End of standard commissioning. Please contact ONICON at (727)447-6140 with any questions.