Product Overview

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Connection to pressure side of lubrication system, OIL
Connection to suction s ide of refrigeration plant, LP
Setting disk (MP 55 and MP 55A)
Reset button
Test device
Product specication
Design and Materials
Figure 4: Design for MP 54, MP 55 and MP 55A
The operation of the pressure switch relies only on the dierential pressure, i.e. the dierence in pressure between
the two counteracting bellows, whereas it is independent of the absolute pressure acting on both bellows.
The MP 55 and 55A can be set for dierent dierential pressures by the setting disc (3).
The set dierential pressure can be read from the internal scale.
The MP 54 has a xed dierential and has no pressure setting disc.
The factory-set dierential pressure is stamped on the front plate of the switch.
Table 1: Materials in contact with the medium
Unit type
Material
MP 54
MP 55
Stainless steel 19/11, no. 1.4306 to EN 10088
Cold forming steel, no. 1.0338, EN 10139
Free cutting steel, no. 1.0718, EN 10277
MP 55A
Stainless steel 19/11, no. 1.4306 to EN 10088
Cold forming steel, no. 1.0338, EN 10139
Free cutting steel, no. 1.0401, EN 10277-2
Technical data
Table 2: Technical data for MP 54, MP 55 and MP 55A
Features
Specications
Control voltage
230 V or 115 V AC or DC
Permissible voltage variation
-15 – 10%
Max. working pressure
PS/MWP = 17 bar
Max. test pressure
P
e
= 22 bar
Ambient temperature
The time relay is temperature-compensated
in the range
-40 – 60 °C
Screwed cable entry
P
g
13.5
Cable diameter
6 – 14 mm
Max. bellows temperature
100 °C
Switch
dierential max. ∆p [bar]
0.2
Dierential pressure switch, Type MP 54, 55 and 55A
© Danfoss | Climate Solutions | 2021.02 AI211986438834en-000901 | 4