Table 9 Zero Corrects Procedure For Std110 - Honeywell ST 3000 Installation Manual

4.1 Mounting ST 3000 Transmitter,
Precautions for
Mounting
Transmitters with
Small Absolute or
Differential Pressure
Spans, continued
28
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 6 for
suggestions on how to level the transmitter using a spirit balance. You
must also zero the transmitter by following the steps in Table 9 below.
Table 9 Zero Corrects Procedure for STD110
Step
Attach the transmitter to the mounting bracket but do not completely
1
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 Figure 1 for
typical SFC connection or connect a voltmeter across the 250 ohm
resistor, if desired.
4 Use the SFC (or SCT) and establish communications with the
transmitter. Follow the steps in Table 2, 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 Do 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
K
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.
Continue with the remaining installation tasks.
9
ST 3000 Release 300 Installation Guide
Continued
Action
SHIFT
J
key. Read applied input pressure.
key. Prompt asks if the applied input pressure equals
key. Zero input is set equal to applied input pressure.
^
key
Continued on next page
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