Filter
Top Products
30 ST 3000 Release 300 and SFC Model STS103 User’s Manual 6/08
4.2 Mounting ST 3000 Transmitter, Continued
ATTENTION
The mounting position of a model STA122, STA922, STA12L, or
STA92L Absolute Pressure Transmitter or a model STD110 Draft
Range Differential Pressure Transmitter is critical as the transmitter
spans become smaller. A maximum zero shift of 2.5 mm Hg for an
absolute transmitter or
1.5 inH
2
O for a draft range transmitter can result from a mounting
position which is rotated 90 degrees from vertical. A typical zero shift of
0.12 mm Hg or 0.20 in H
2
O can occur for a 5 degree rotation from
vertical.
Precautions for
Mounting
Transmitters with
Small Absolute or
Differential Pressure
Spans
To minimize these positional effects on calibration (zero shift), take the
appropriate mounting precautions that follow for the given transmitter
model.
For a model STA122, STA922, STA12L, or STA92L transmitter, 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.
Figure 9 Leveling an Absolute Pressure Transmitter.
Leveling Absolute Pressure models
Center
Section
Process
Head
Position spirit balance on
center section of meter
body only.
Cont’d
Continued on next page