Mechatronic
pressure measurement
Pressure switch mechanical
Model PSM-550
Switzer data sheet PSM-550
Applications
■■ Pumps, filters
■■ Vacuum brakes
■■ Lubrication system, hydraulic system
■■ HVAC
■■ Circuit breakers
■■ Heat exchanger, water treatment
Special features
■■ Wide adjustable range
■■ Adjustable on-off differential
■■ Sturdy snap action switch
■■ Repeatability ±1%
■■ Weatherproof to IP67
Pressure switch mechanical, model PSM-550
Description
PSM-550 pressure switches utilise seamless bellows as the Applications include pumps, compressors, filters,
sensing element. Simplicity of design and easy of installation evaporators, heat exchangers, lubrication systems, hydraulic
has been stressed for reliable use, even in applications systems, marine equipment, heating and air conditioning
where shock and vibrations are present. The sensing equipment, turbines, generators and circuit-breakers etc.
element is suitable for a variety of process fluids.
PSM-550 switches have an excellent record backed by
our responsive manufacturing facility. Special application
assistance is always available.
Switzer data sheet PSM-550 ∙ 01/2021 Page 1 of 4
Standard version
Switch enclosure Switch contacts
Cover: ABS, plastic One SPDT contact system
Housing: Polyester
On-off differential
Repeatability Adjustable
±1 % of full scale value
Electrical rating
Permissible ambient temperature ■■ AC-1: 10A, 230V
-25 °C ... +70 °C ■■ AC-15: 4A, 230V
Permissible medium temperature Electrical entry
■■ -20 °C ... +70 °C for code 11 and 41
1/2" NPT(F)
■■ -20 °C ... +170 °C for code 44 and 22
Ingress protection
IP67
Process connection
■■ 3/8" BSP(M)
Mounting
Direct online
Measuring element
■■ Bellows Conformity
■■ NBR (Nitrile) diaphragm for PSM-550-M1 Generally to BS:6134:1991
Pressure connector Options
■■ One SPDT microswitch
■■ Brass (standard)
15A resistive AC 250 V
■■ Mild steel for PSM-550-M1 (standard)
0.5A 110V / 0.25A 220V / 8A 24V:DC-resistive
■■ 304 or 316 stainless steel
0.2A 110V / 0.10A 220V / 7A 24V:DC-Inductive
■■ DPDT microswitch
Gasket 10A AC 125 / 250 V,
Process connection: Nitrile 2A AC 480 V, 0.25A DC 250 V
Cover: Silicone
Ordering matrix
Maximum working pressure
Differential in bar
Range in bar
Model
in bar Contact system/ D type
11 41
S type microswitch microswitch
PSM-550–C1 (–) 0.8 ... 5 0.5 ... 2 0.5 ... 2 15 25
PSM-550–V1 (–) 1 ... 0 0.09 ... 0.4 0.18 ... 0.49 7 7
PSM-550–B1 0.1 ... 1.1 0.07 ... 0.16 0.14 ... 0.23 7 7
PSM-550–B2 0.2 ... 3 0.12 ... 0.75 0.25 ... 1.1 7 7
PSM-550–B3 0.2 ... 6 0.25 ... 1.2 0.5 ... 1.45 15 25
PSM-550–B4 1 ... 10 0.3 ... 1.3 0.6 ... 1.6 16 25
PSM-550–B5 Ø 2 ... 17 0.3 ... 2 0.6 ... 2.3 --- 25
PSM-550–B6 4 ... 17 1.2 ... 4 2.4 ... 5.2 25 25
PSM-550–B7 10 ... 30 1 ... 4 2.0 ... 5.0 45 45
Maximum working pressure
Differential in cmWc
in bar
Model Range in cmWC
Contact system/ D type
NC
S type microswitch microswitch
PSM-550–M1 0 ... 300 10 ... 50 20 ... 60 0.5
Ø PSM-550–B5 is not available with phosphor bronze bellows.
Page 2 of 4 Switzer data sheet PSM-550 ∙ 01/2021
Ordering matrix continued
Sensing element and pressure connector Model Number to be ordered as below
11 PB bellows with brass pressure connector (standard)
Sensing element
Contact Switch
Type and pressure
41 304 SS bellows with brass pressure connector version enclosure
connector
44 304 SS bellows with 304 SS pressure connector
22 316 SS bellows with 316 SS pressure connector
(for model PSM-550-B3, B4, B5 and B6 only) Example: PSM-550–B4–41–S–A
NC Nitrile diaphragm with mild steel pressure connector
Type PSM-550–B4 (range 1 to 10 bar)
(for model PSM-550-M1 only)
304 SS bellows with brass pressure connector
Contact version
SPDT microswitch 15A resistive AC 250V
C One SPDT contact system
Aluminium, powder coated cover with Die cast aluminium
S One SPDT microswitch housing, weatherproof to IP66 as per IS/IEC:60529-2001
D DPDT microswitch
Switch enclosure
D ABS, plastic cover with polyester housing,
weatherproof to IP67 as per IS/IEC:60529-2001
(standard)
A Aluminium, powder coated cover with Die cast
aluminium housing, weatherproof to IP66 as per IS/
IEC:60529-2001
Switzer data sheet PSM-550 ∙ 01/2021 Page 3 of 4
Dimensions in mm
PSM–550–C1
PSM–550–M1 PSM–550–V1 PSM–550–B2
PSM–550–B1 PSM–550–B3
PSM–550–B4
PSM–550–B5
PSM–550–B6
PSM–550–B7
Ordering information
Type / Sensing element and pressure connector / Contact version / Switch enclosure
2018 Switzer Process Instruments Pvt. Ltd., all rights reserved.
The specifications given in this document represent the state of engineering at the time of publishing.
We reserve the right to make modifications to the specifications and materials.
Switzer data sheet PSM-550 ∙ 01/2020 Page 4 of 4
Switzer Process Instruments Pvt. Ltd.
128 SIDCO North Phase,
Ambattur Industrial Estate, Chennai 600 098
Tel. +91 44 2625 2017 / 2018 / 4991 / 4324
sales@switzerprocess.co.in
www.switzerprocess.co.in
Works
C-123, Site No.1, Industrial Area
Bulandshahar Road, Ghaziabad 201 009
