Table 10 Zero Corrects Procedure For Std110 - Honeywell ST 3000 User Manual

4.2 Mounting ST 3000 Transmitter,
Precautions for
Mounting
Transmitters with
Small Absolute or
Differential Pressure
Spans, continued
32 ST 3000 Release 300 and SFC Model STS103 User's Manual
For a transmitter with a small differential pressure span, you must
ensure that the transmitter is vertical when mounting it. You do this by
leveling the transmitter side-to-side and front-to-back. See Figure 9 for
suggestions on how to level the transmitter using a spirit balance. You
must also zero the transmitter by following the steps in Table 10 below.
Table 10 Zero Corrects Procedure for STD110
Step
1 Attach the transmitter to the mounting bracket but do not completely
tighten the mounting bolts
2 Connect a tube between the input connections in the high pressure
(HP) and low pressure (LP) heads to eliminate the affects of any
surrounding air currents.
Connect 24 Vdc power to the transmitter and connect a digital
3
voltmeter or SFC to read the transmitter's output. See Figures 18
and 38 for typical SFC connection or connect a voltmeter across the
250 ohm resistor, if desired.
4 Use the SFC and establish communications with the transmitter.
Follow the steps in Table 17, if needed.
While reading the transmitter's output on an SFC or a voltmeter,
5
position the transmitter so the output reading is at or near zero and
then completely tighten the mounting bolts.
6 Perform an input zero correct function using the SFC and following
the steps below. This corrects the transmitter for any minor error that
may occur after the mounting bolts are tightened.
7
Initiate shift key selection. Press
INPUT
OUT-
PUT
Press
RESET
COR-
RECT
Press
zero input. If it is zero input, go to next keystroke. If it is not, press
[ ] key to exit function and repeat keystrokes.
CLR
NON-VOL
ENTER
(Yes)
Press
8 Remove the tube from between the input connections, the power,
and the digital voltmeter or SFC.
9 Continue with the remaining installation tasks.
Continued
Action
SHIFT
J
key. Read applied input pressure.
K
key. Prompt asks if the applied input pressure equals
key. Zero input is set equal to applied input pressure.
^
key
Continued on next page
February 2012