Pneumatic Pilot Controllers

LAP, LAPB, LAUP, LAUPB, LA, LAB, LAU and LAUB Leslie-Levelmatic Liquid Level Pilot Controllers

3 - 15 Psig Output Fixed or Proportional Band
Bi-Metallic or Liquid Filled Temperature Element

Leslie-Levelmatic pilot controllers use a simple, stable, floatless differential pressure sensing principle. They require only two simple connections to the vessel (open or closed). Standard units come in two sensing ranges: 0 to 36 inches and 0 to 200 inches(H20). Normal operating pressure is 10-22 psi. Static pressure on the sensing diaphragm can be anywhere within the range of 30" Hg vacuum to 300 psig. Options include fixed or proportional band.


PRA, PRAP, PDA, PDAP, PRQ and PDQ Constant Pressure Pilot Controllers

These pilot controllers use an inherently stable force-balanced design

and provide high speed response, exceptional reliability and high

output volume. Normal operating pressure is 20 to 22 psig, maximum static pressure is 900 psig and the adjustable range is 13 psia to 800 psig.


BP, BPC, RTP and DTP Constant Temperature Pilot Controllers

Leslie constant temperature pilot controllers deliver an air signal to a control valve or other control element in response to a change in sensed temperature. They are available with

a bi-metallic thermal element or a factory-sealed liquid-filled bulb. Both types are shock resistant, corrosion resistant and highly reliable.

Liquid-filled thermo-element types convert temperature to a proportional pneumatic signal which is used to operate a control valve. These units are available with adjustable proportional band and optional calibrated dials in Fahrenheit or Celsius. Sensing range is 20°F to 400F (-7C to 205C).

The bi-metallic sensing element types are widely employed in heating or cooling service. Bi-metallic pilot controllers respond to minute changes in sensed temperature and provide accurate stable control. They are unaffected by moisture or oil in the air supply. Sensing range is 32F to 600F (0C to 315C).