ProportionAir ISQB1, Installation & Maintenance Instructions Manual

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10 ISQB1 Installation Guide - 2/13/2015 | SSS
5. Set the electrical command input to 20mADC. Adjust
the SPAN potentiometer until MAXIMUM desired
pressure is reached (clockwise to increase pressure).
6. Set the electrical command input to 10 percent of full
value (5.6mA).
7. Adjust the ZERO potentiometer until 10 percent of
maximum desired pressure is reached. (clockwise
increases pressure).
8. The ZERO and SPAN potentiometers interact slightly.
Repeat steps 5-10 until no error exists.
9. Verify unit shuts off by going to 4mADC command.
Check linearity by going to at least six pressures
throughout the full range.
NOTE: Only use this step if your device is totally
out of calibration. If it is slightly out of calibration,
omit this step and move on to paragraph 5. Using a
small screwdriver, turn both potentiometers 15 turns
clockwise. Then turn them 7 turns counter clockwise.
This will put the ISQB1 roughly at mid scale.
Re-calibration:
1. Wire the ISQB1 according to the section titled
“Electrical Connections.”
2. Connect a precision pressure gage or pressure
transducer to the OUTLET PORT of the ISQB1.
NOTE: There must be a closed volume of at least
1 in
3
between the OUTLET PORT and the measuring
device for the ISQB1 to be stable.
3. Provide supply pressure to the INLET PORT of the
ISQB1. (See figure 1). Make sure supply pressure
does not exceed the rating for the valve. (see table 1)
All ISQB1 valves come calibrated from the factory by
trained personnel using precision calibration equipment.
The ISQB1 is a closed loop control valve using a
precision electronic pressure sensor. Typical drift is less
than 1% over the life of the product. If your ISQB1
appears to be out of calibration by more than 1%, it is not
likely to be ISQB1. Check the system for plumbing
leakage, wiring and electronic signal levels. Verify the
accuracy of your measuring equipment before re-
calibrating. If the ISQB1 valve needs re-calibration, use
the procedure described below:
RE-CALIBRATION PROCEDURE
4. Remove the zero and span plug on top of the ISQB1
to access the ZERO and SPAN adjustment
potentiometers (figure 1).
ISQB1 & BRACKET DIMENSIONS