User Manual

I/P TRANSDUCERS
The “standard” 3-15 psi signal was originally designed as a transmission
signal, not a valve actuation signal. The Fluid Controls Institute (in
Standard 87-2) has recommended that a 1–17 psi air signal range be used
when directly actuating a control valve without a positioner. Powers
concurs with this recommendation, and therefore, offers a 1–17 psi I/P
transducer and a 0–30 psi I/P transducer and the Accritem pneumatic
controller for maximum close-off. 3-15 psi I/P transducers should be used
in conjunction with positioners.
POSITIONERS
Positioners are used for one or more of the following reasons:
1) To split range valves.
2) To eliminate unwanted valve movement caused by line pressure
variations
3) To minimize the effects of “stick-slip”
4) To speed response time
5) To increase close-off rating when I/Ps are used.
Page 8 TI597SI
CODE PNEUMATIC DIAPHRAGM ACTUATORS
4C 46 Sq. In., 1” Max Valve Stroke Extreme Cycle Springs,
adjustable start w/6-12 lb. fixed span.
1U (for 6" valve only) 100 Sq. In; 8-13 psi Spring Range, (Normally Closed Valves)
1L (for 6" valve only) 100 Sq. In; 3-8 psi Spring Range, (Normally Open Valves)
CODE DESCRIPTION
Bellofram 1000 I/P’S
IS 3–15 psi
TS 1–17 psi
US 3–27 psi
CONTROL/AIR TYPE 900X I/P
ES 0–30 psi
UTILITY POSITIONER AND I/P
BS 4–20 mA
UTILITY POSITIONER
PS 3-15 psi
RS 3-9 psi
SS 9-15 ps
NO ACCESSORIES
OS No Accessories
ACCESSORIES SELECT CODE
ACTUATOR SELECT CODE
ORDERING INFORMATION
© 2007 Powers
USA: Phone: [phone] • Fax [phone] . 0526 • www.powerscontrols.com
Canada: Phone: [phone] • Fax [phone] • www.powerscontrols.ca
TI597SI 0708 EDP# 6512273