Eletta PR1 User manual

PR1 liquid flow switch
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Manual
PR1

PR1 liquid flow switch
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Function
The PR1 liquid flow switch is suitable for control and monitoring in installations where a
functional value (impulse transmission) from 100 l/min and upwards is acceptable.
The function value is dependent on the pipe dimension and paddle length. The lowest functional
value (switching value) that can be obtained in a 50 pipe is about 90 l/min = 0.7 m/sec. For a 150
pipe, the corresponding value is about 240 l/min = 0.2 m/sec.
The paddle is lodged so that it can be folded in either direction. It always moves in the direction
of the flow and can therefore never be damaged due to possible recoil shocks. However, the
contact function only occurs in the pre-determined direction of flow.
The movement of the paddle with the flow affects a lever that actuates a built-in micro-switch.
The paddle length determines the signal point at which the switch changes position.
As standard, the parts wetted by liquid are made of a copper alloy and stainless steel. The paddle
is suspended in teflon bearings. Sealing sleeve for pivoting Nitrile bushing (HNBR).
Model
PR1 can be used for pipe sizes 2” –10”.
The PR1 has a built-in micro-switch with alternating contact function.
Installation instructions
The PR1 is mounted in a 1” half sleeve on the pipe.
The position of the switch is fixed and can only be mounted in horizontal lines with the
impulse cover facing upwards.
Make sure that the direction of flow is aligned with the arrow on the bottom plate under
the cover.
When mounting, make sure that the flow is
in the direction of the arrow.

PR1 liquid flow switch
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There should be a straight pipe section about 3 times the pipe diameter before and after
the switch.
The switch is supplied with a paddle for 10”. Cut the paddle to the desired pipe size
before mounting; see the table below.
Max. paddle length
Pipe size
L mm
2”
50
22
2 ½”
65
38
3”
80
52
4”
100
75
5”
125
100
6”
150
125
8”
200
175
10”
250
200
PR1 specifications
Alarm point: Not exact. The switch is only used to indicate flow or no flow.
Connections: 1” half sleeve on pipe size from DN50.
Max. pressure: 25 bar
Max. fluid temperature: 125 °C
Min. liquid temperature: –20 °C
Protection class: IP 65 with M16 GR cable gland included.
Wetted materials: Dezincification-resistant brass, stainless steel 316 and PTFE
Nitrile (HNBR) seals. Optional EPDM and FPM (Viton)
Enclosure material: Polycarbonate (Lexan®)
Micro-switch: SPDT, 1-pole 2-way connector. In the standard design, the contact
surfaces are silver-plated. Max. load 250 V/8 A Nominal,
250 V/10 A Thermal.
Micro-switch
change-over
Switch-on
l/min
Switch-off
l/min
DN 50
> 125
<75
DN 65
> 150
< 100
DN 80
> 200
< 150
DN 100
> 300
< 200
DN 150
> 350
< 250
Note: Only approximate
values!

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Electrical data
PR1 micro-switch
Contact function 1 pole, 2-way
Dimensions and weight
Weight: 0.7 kg
Eletta Flow AB
Box 5084
SE-141 05 Kungens Kurva, Sweden
08 –603 07 70
[email protected] www.eletta.com
Proprietary Rights
This manual contains confidential technical data, including trade secrets and proprietary information, which are the property of Eletta Flow AB, Sweden.
Any changes or alterations to downloaded or printed Eletta original documentation such as manuals, drawings, leaflets, newsletters, etc, are not permitted without written
permission from Eletta Flow AB, Sweden. This data is only disclosed to you under the permission of limited use within your company. Use for manufacturing or processing is not
permitted. Any other use of data and information is strictly prohibited without prior written permission from Eletta Flow AB, Sweden.
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