Honeywell SMV 3000 - Manual (Page 35)

1/99 SMV 3000 Transmitter User’s Manual 23
4.2 Mounting SMV 3000 Transmitter,
Continued
ATTENTION The mounting position of an SMV 3000 Transmitter is critical as the
transmitter spans become smaller for the absolute and/or differential
pressure range. A maximum zero shift of 0.048 psi for an absolute
pressure range or 1.5 in H
2
O for a differential pressure range can result
from a mounting position which is rotated 90 degrees from vertical. A
typical zero shift of 0.002 psi or 0.20 in H
2
O can occur for a 5 degree
rotation from vertical.
Precautions for
Mounting
Transmitters with
Small Differential
Pressure Spans To minimize these positional effects on calibration (zero shift), take the
appropriate mounting precautions that follow for the given pressure range.
•
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 adjusting the mounting position
of the transmitter. Refer to start-up procedure in Section 7 for SMV
3000 transmitter model SMA110 and transmitters with small
differential pressure spans.
Figure 9 Leveling a Transmitter with a Small Absolute Pressure Span.
Process
Center
Section
Head
Spirit
Balance