EN
Operating instructions
14306499.01 02/2019 EN
WIKA Alexander Wiegand SE & Co. KG
Alexander-Wiegand-Straße 30
63911 Klingenberg • Germany
Tel. +49 9372 132-0
Fax +49 9372 132-406
www.wika.de
© 02/2019 WIKA Alexander Wiegand SE & Co. KG
All rights reserved.
WIKA
®
is a registered trademark in various countries.
Prior to starting any work, read the operating instructions!
Keep for later use!
Contents
Declarations of conformity can be found online at www.wika.com.
1. General information
2. Design and function
3. Safety
4. Transport, packaging and storage
5. Commissioning, operation
6. Faults
7. Maintenance and cleaning
8. Dismounting, return and disposal
9. Specifications
Pressure switch, high adjustability of switch differential
For the process industry
Model PSM-700
WIKA operating instructions, pressure switch, high adjustability of switch differential, model PSM-700
1. General information
■
The mechanical pressure switch described in the operating instructions has been
designed and manufactured using state-of-the-art technology. All components
are subject to stringent quality and environmental criteria during production. Our
management systems are certified to ISO 9001.
■
These operating instructions contain important information on handling the instru-
ment. Working safely requires that all safety instructions and work instructions are
observed.
■
Observe the relevant local accident prevention regulations and general safety
regulations for the instrument’s range of use.
■
The operating instructions are part of the product and must be kept in the immedi-
ate vicinity of the pressure measuring instrument and readily accessible to skilled
personnel at any time.
■
Skilled personnel must have carefully read and understood the operating instruc-
tions prior to beginning any work.
■
The manufacturer‘s liability is void in the case of any damage caused by using
the product contrary to its intended use, non-compliance with these operating
instructions, assignment of insufficiently qualified skilled personnel or unauthorised
modifications to the instrument.
■
The general terms and conditions contained in the sales documentation shall apply.
■
Subject to technical modifications.
■
Further information:
- Internet address:
www.wika.de / www.wika.com
- Relevant data sheet:
PV 35.05
Abbreviations, definitions
DPDT Double pole double throw
SPDT Single pole double throw
NC
Normally closed contact type (NC = normally closed)
NO
Normally open contact type (NO = normally open)
COM Common contact
GND Ground connection
2. Design and function
2.1 Overview
2.2 Description
The pressure element of the model PSM-700 is a resilient bellow from stainless steel
which works against a spring mechanism with an adjustable pre-load force. On the
spring mechanism there is a contact arm for actuating the switch contact. The switch
is actuated as soon as the force generated by the pressure in the pressure element is
greater than the set pre-load force.
2.3 Terms used
Maximum operating pressure
The maximum static pressure with which the instrument can be used without changing
the assured performance data.
Reset point
The pressure value at which the switch returns to the starting position. Mathematically,
the pressure value for the reset point is equal to the pressure value of the switch point
minus the switch differential on rising pressure. On falling pressure, the pressure value
for the reset point is equal to the pressure value of the switch point plus the switch
differential.
Switch differential
The switch differential is the difference between the switch point and the reset point.
This is also known as the switch hysteresis.
2.4 Scope of delivery
Pressure switch, operating instructions
Cross-check scope of delivery with delivery note.
Switch differential setting (option)
Blow-out device
Electrical connection 1, lateral
Electrical connection 2, top
(only for DPDT or option)
Removable cover
Switch point setting
Locking plate with screw (tamper proofing)
Switch point setting display
Process connection
