General Information; Mechanical Installation - Setra Systems 267 Operating Instructions Manual

1.0 General information

Every model 267 and Model 267MR (multi-range) has been tested and calibrated before
shipment. Specific performance specifications are listed on page 9 of this guide.
The model 267 is single range only. The model 267MR has field selectable range capability.
The 267MR is factory calibrated for the highest pressure range. The range label on the cover
of the unit indicates the factory-calibrated range. Should the 267MR be re-ranged in the field,
other multi-range labels are included.
Setra Systems 267 and 267MR pressure transducers sense differential or gauge (static)
pressure and convert this pressure difference to a proportional high level analog output for both
unidirectional and bidirectional pressure ranges. Two output versions are offered: A configurable
voltage output of 0 to 5 VDC or 0 to 10 VDC, and a current output of 4 to 20 mA.
Sections 1 through 4 and 7 through 9 of this guide apply to both models 267 and 267MR.
Section 5 refers to the model 267 only. Section 6 refers to the model 267MR only.

2.0 Mechanical installation

2.1 Media compatibility
Model 267 and 267MR transducers are designed to be used with air or nonconducting gases.
Use with liquids or corrosive gases will damage the unit.
2.2 Environment
The operating temperature limits of the 267 and 267MR are as follows:
Operating temperature
Compensated temperature range
2.3 Pressure fittings
The Model 267 and 267MR can be supplied with three different pressure fitting configurations:
A. 3/16" O.D. Barbed brass pressure fittings – Typically installed with 1/4" push-on tubing
B. 1/4"NPT Brass pressure fittings – Typically installed with mating NPT male fitting.
C. Static pressure probe – Installed on the duct by drilling a 7/16" hole in the duct at the
desired mounting location, inserting the pressure probe into the duct, and mounting the
267 onto the duct with the mounting tabs.
For the 3/16" O.D. and 1/4" NPTF pressure fittings, both the positive (high) pressure port and
the reference (low) pressure port are located on the bottom of the unit, labeled "high" and "low"
respectively. For the best results (shortest response times), 3/16" I.D. for tubing is suggested
for tubing lengths up to 100 feet long, 1/4" I.D. for tubing lengths up to 300 feet, and 3/8" I.D.
for tubing lengths up to 900 feet.
The static pressure probe is positive (high) pressure port located on the back of the unit. The
reference (low) pressure port is located on the bottom of the unit and can be used for differential
pressure measurements.
0°F to +150°F (-18°C to +65°C)
+40°F to +150°F (+5°C to +65°C)