Pressure switches from Johnson Controls

Published:  19 January, 2008

Johnson
Versatile pressure control — the P77 series of pressure switches from Johnson Controls.

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

comments powered by Disqus

Search

Welcome

Welcome to Modern Building Services Online, the web edition of Modern Building Services (MBS) journal and the UK's most popular Building Services engineering site. Modern Building Services covers the entire Building Services Engineering industry. This site contains archived content from the journal, plus web-specific content.

When you go to our digital edition, you can also access the archive of digital editions.
April 2017: DIGITAL EDITION
ARCHIVE OF DIGITAL EDITIONS

Modern Building services has a group
on Linkedin - join us!

Jobs

  • Compliance Manager

    Working in the Estates Facilities Management Hard Services Team, directly line manage the Compliance Team of 8 staff. Ensure University building services and infrastructure are legally compliant and fit for purpose, to enable research, teaching and learn.........

  • Estates Project Manager (NHS)

      Working as part of the Hampshire Hospitals NHS Foundation Trust   Estates team, you will be responsible for developing capital projects from feasibility studies, through to delivery of refurbishments, backlog maintenance schemes and new builds. .........

more jobs »

Poll

"Is the Building Services industry lagging behind in the implementation of BIM?"



Calendar