Pressure switches from Johnson Controls
Published: 19 January, 2008
Johnson Controls has launched a range of pressure switches for refrigeration, air-conditioning and heat-pump applications that conform to PED 97/23/EC Cat IV.
P77 series single pressure controls have a range of 3 to 42 bar and can be used in a variety of applications involving high- or low-pressure refrigeration. They are IP54 classified. These switches can be used with R22, R134a, R404A, R410A and all other non-corrosive refrigerants within the operating range of the control — plus other high- or low-pressure applications such as air and water.
The controls are provided with a special power element, with external pressure on the bellows instead of internal pressure like the present standard versions. All models have alarm contacts, and standard models have phosphor-bronze bellows and brass pressure connections. They can be used for control functions or limit functions.
SPDT contacts are standard, so the P77 series can be wired for alarm functions. Trip-free manual reset ensures over-ride is not possible in the control function.For more information on this story, click here:Jan 08, 168
- 23 October, 2014, 9:30 - 17:30Training Day 1: What Data?
- 28 - 29 October, 2014Leadership in building performance
- 05 - 06 November, 2014FutureBuild 2014
- 05 November, 2014 - 15:15Heat 2014
- 11 November, 2014Heat metering for the Renewable Heat Incentive
- 14 November, 2014BSRIA Briefing — Smarter ways to better buildings
- 18 November, 2014Biomass heating
- 20 November, 2014KNX seminar
- 25 November, 2014Implementing BIM — preparing your implementation plan
- 26 - 27 November, 2014Resilience14
- 27 November, 201410-80-10 — The Building Services Summit