Filter
Top Products
Instruction Manual
245364-V
May 2002
A-2 Appendix A – Vaisala Pressure Transducer Rosemount Analytical Inc. A Division of Emerson Process Management
Model 755A
A-4 ADJUSTMENT
Circuit adjustment can be made using the built
in display together along with a Digital
voltmeter.
1. Select position 2 on the front panel selector
switch. Connect the DVM (+) to TP1, (-) to TP2
on the INTERFACE Board. Adjust for zero volts
as closely as possible using potentiometer VR1
(DMM set to the mVDC range) on this same
board.
2. Move the DVM to (TP) 14 and ground (TP10).
Adjust the AD625 zero offset adjustment for the
lowest zero voltage output. Note! All these
adjustments are made at ambient pressure and
the display on position 2 should now read zero.
The noise should be less than ±1 count.
Procedure is complete.
A-5 HIGH ALTITUDE VERSION OPTION
For applications where the instrument is to be
used above 5400 Feet (MSL) an alternate
transducer option is available from the factory.
This version consists of a Vaisala model
PTB100B transducer (900-1100 hPa range),
and an interface board with modified values
for resistors R2 and R4. Contact Rosemount
Customer Service Center if you require this
option.