Bühler technologies MDS Series User manual

Fluidcontrol
Installation and Operation Instructions
Original instructions
Mechanical Pressure Switch
MDS
BE130006
03/2019
Bühler Technologies GmbH, Harkortstr. 29, D-40880 Ratingen
Tel. [phone] / 49 89-0, Fax: [phone] / 49 89-20
E-Mail: [email protected]
Internet: www.buehler-technologies.com

Bühler Technologies GmbH, Harkortstr. 29, D-40880 Ratingen
Tel. [phone] / 49 89-0, Fax: [phone] / 49 89-20
Internet: www.buehler-technologies.com
E-Mail: [email protected]
Read this instruction carefully prior to installation and/or use. Pay at-
tention particularly to all advises and safety instructions to prevent in-
juries. Bühler Technologies can not be held responsible for misusing
the product or unreliable function due to unauthorised modifications.
All rights reserved. Bühler Technologies GmbH 2019
Document information
Document No..........................................................BE130006
Version......................................................................... 03/2019

MDS
Contents
1 Introduction..................................................................................................................................................................................................................... 2
1.1 Intended Use.........................................................................................................................................................................................................2
1.2 Contents................................................................................................................................................................................................................. 2
1.3 Ordering instructions ........................................................................................................................................................................................ 2
1.3.1 Model key MDS......................................................................................................................................................................................2
1.3.2 Model key MDSM and MDSK.............................................................................................................................................................3
2 Safety instructions.........................................................................................................................................................................................................4
2.1 Important advice .................................................................................................................................................................................................4
2.2 General hazard warnings .................................................................................................................................................................................4
3 Transport and storage ..................................................................................................................................................................................................6
4 Installation and connection ........................................................................................................................................................................................ 7
4.1 Area of application.............................................................................................................................................................................................. 7
4.2 Installation ............................................................................................................................................................................................................ 7
5 Operation and control ..................................................................................................................................................................................................8
5.1 Setting the switching point and hysteresis on model MDS....................................................................................................................8
5.2 Setting the switching point on models MDSM and MDSK .....................................................................................................................9
6 Service and repair......................................................................................................................................................................................................... 10
7 Disposal............................................................................................................................................................................................................................ 11
8 Appendices......................................................................................................................................................................................................................12
8.1 Technical Data MDS.......................................................................................................................................................................................... 12
8.2 Technical Data MDSM and MDSK..................................................................................................................................................................13
8.3 Dimensions MDS ............................................................................................................................................................................................... 14
8.4 Dimensions MDSM and MDSK ...................................................................................................................................................................... 14
9 Attached documents................................................................................................................................................................................................... 16
iBühler Technologies GmbHBE130006 ◦ 03/2019

MDS
1 Introduction
1.1 Intended Use
The operating instructions apply to MDSxxx series mechanical pressure switches.
The pressure switches are used to monitor the pressure in a fluid system under normal ambient conditions. As electromechan-
ical signal converter they convert the pressure into electrical signals with high precision. They detect pressure ranges from
0.5bar to max. 320bar in different combinations. Depending on the version, the process connection is a G1/8" or G1/4" external
thread, a G1/4" internal thread, or a flange (VF). They connect to power via M3 cubic plug (DIN EN 175301-803) or M12x1 plug (elec-
tric line box not included).
1.2 Contents
– MDS Mechanical Pressure Switch
– Product Documentation
1.3 Ordering instructions
1.3.1 Model key MDS
MDS
Series
Plug connection
M3 or M12
Fluid connection
G1/8" or G1/4"
Pressure ranges
Switching point setting
Pressure ranges
8:
16:
120:
250:
320:
0.5...8 bar
1...16 bar
10...120 bar
20...250 bar
30...320 bar
Membrane switch
Membrane switch
Piston pressure switch
Piston pressure switch
Piston pressure switch
1) (optional)
1) If necessary, the switching point can be set at the factory. The switching point must be selected with the pressure rising or fall-
ing, i.e. switching point from 0 bar to switching point (rising) or from the max. operating pressure to the switching point (fall-
ing). Please refer to the following example for the switching logic:
MDS-M3-G1/4-120-80R (switching point 80 bar rising):
Pin3-2 closed when switching point reached
MDS-M3-G1/4-120-80F (switching point 80 bar falling):
Pin3-1 closed when switching point reached
2 Bühler Technologies GmbH BE130006 ◦ 03/2019

MDS
1.3.2 Model key MDSM and MDSK
MDS
Series
M
K
MDSM
MDSK
Plug connection
M3 or M12
Thread / connection
G 1/4i
G 1/4d
VF
Pressure ranges
Switching point setting1)
Pressure ranges
8:
16:
120:
250:
320:
0.5...8 bar
1...16 bar
10...120 bar
20...250 bar
30...320 bar
MDSM
MDSM
MDSK
MDSK
MDSK
G 1/4" internal (only MDSM)
G 1/4" swivel (only MDSK)
Vertical flange per ISO 1673 (only MDSK)
1) If necessary, the switching point can be set at the factory. The switching point must be selected with the pressure rising or fall-
ing, i.e. switching point from 0 bar to switching point (rising) or from the max. operating pressure to the switching point (fall-
ing). Please refer to the following example for the switching logic:
MDSK-M3-G1/4-120-80R (switching point 80 bar rising)
PIN1-3 closed when switching point reached
MDSK-M3-G1/4-120-80F (switching point 80 bar falling)
PIN1-2 closed when switching point reached
3Bühler Technologies GmbHBE130006 ◦ 03/2019

MDS
2 Safety instructions
2.1 Important advice
Operation of the device is only valid if:
– the product is used under the conditions described in the installation- and operation instruction, the intended application
according to the type plate and the intended use. In case of unauthorized modifications done by the user Bühler Technolo-
gies GmbH can not be held responsible for any damage,
– when complying with the specifications and markings on the nameplates.
– the performance limits given in the datasheets and in the installation- and operation instruction are obeyed,
– monitoring devices and safety devices are installed properly,
– service and repair is carried out by Bühler Technologies GmbH,
– only original spare parts are used.
This manual is part of the equipment. The manufacturer keeps the right to modify specifications without advanced notice. Keep
this manual for later use.
Signal words for warnings
DANGER
Signal word for an imminent danger with high risk, resulting in severe injuries or death if not avoided.
WARNING
Signal word for a hazardous situation with medium risk, possibly resulting in severe injuries or death if not
avoided.
CAUTION
Signal word for a hazardous situation with low risk, resulting in damaged to the device or the property or
minor or medium injuries if not avoided.
NOTICE
Signal word for important information to the product.
Warning signs
These instructions use the following warning signs:
Warns of a general hazard General information
Voltage warning Unplug from mains
High pressure warning
2.2 General hazard warnings
The equipment must be installed by a professional familiar with the safety requirements and risks.
Be sure to observe the safety regulations and generally applicable rules of technology relevant for the installation site. Prevent
malfunctions and avoid personal injuries and property damage.
The operator of the system must ensure:
– Safety notices and operating instructions are available and observed,
– The respective national accident prevention regulations are observed,
– The permissible data and operational conditions are maintained,
– Safety guards are used and mandatory maintenance is performed,
– Legal regulations are observed during disposal,
– compliance with national installation regulations.
4 Bühler Technologies GmbH BE130006 ◦ 03/2019

MDS
Maintenance, Repair
Please note during maintenance and repairs:
– Repairs to the unit must be performed by Bühler authorised personnel.
– Only perform conversion-, maintenance or installation work described in these operating and installation instructions.
– Always use genuine spare parts.
Always observe the applicable safety and operating regulations in the respective country of use when performing any type of
maintenance.
5Bühler Technologies GmbHBE130006 ◦ 03/2019

MDS
3 Transport and storage
Only transport the product inside the original packaging or a suitable alternative.
The equipment must be protected from moisture and heat when not in use. It must be stored in a covered, dry, dust-free room
at room temperature.
6 Bühler Technologies GmbH BE130006 ◦ 03/2019

MDS
4 Installation and connection
4.1 Area of application
WARNING
All device models are solely intended for industrial applications. They are not safety com-
ponents. The devices must not be used if failure or malfunction thereof jeopardises the
safety and health of persons.
Use in explosive areas is prohibited.
DANGER Explosion hazard when used in Ex explosive areas
Use in explosive areas is prohibited.
Before installing the device, please verify the listed technical data meet the application parameters. Further verify all contents
are complete.
4.2 Installation
The device must be connected and installed by a trained professional. Always observe the applicable safety regulations for the
operating site!
DANGER Electric voltage
Risk of electric shock
a) Disconnect all poles of the unit from the mains for any maintenance on electric com-
ponents.
b) Secure the equipment from accidental restarting.
c) The unit may only be opened by trained, competent personnel.
d) Ensure the correct voltages supply.
WARNING Gases or liquids discharged under pressure
Depressurise the system before installing or removing the pressure switch.
The process connects as specified:
MDS G1/8" or G1/4" external thread
MDSM G1/4" internal thread
MDSK G1/4" swivel or vertical flange (VF)
It connects to electricity via M3 or M12 plug connection with the following assignment:
Plug connection M3 (DIN EN 17505-803), 3-pin + PE M12 (base) 4-pin
Max. voltage 250 V 28 V
IP rating IP65 IP67 (with suitable line socket)
Cable fitting PG9
Pin assignment MDS
Pin assignment MDSM
MDSK
7Bühler Technologies GmbHBE130006 ◦ 03/2019

MDS
5 Operation and control
5.1 Setting the switching point and hysteresis on model MDS
The hysteresis is defined as the difference between the switching point and switch-back point. It is the result of mechanical fric-
tion of the pressure sensor caused by flow forces and the spring.
Hysteresis on membrane version MDS
Switching point (bar)
Hysteresis (bar)
Hysteresis on piston version MDS
Switching point (bar)
Hysteresis (bar)
Switch-back point
Switch-back point with falling pressure
Switching point or
Hysteresis
Pressure
Switching point with rising pressure
– Disconnect the pressure switch from the power supply
– Whilst monitoring the pressure gauge on the system, set the switching point with a hexagon
key.
– Adjust the hysteresis with a screwdriver. Turning clockwise increases, turning anti-clockwise
decreases the value.
– Reconnect the power plug.
8 Bühler Technologies GmbH BE130006 ◦ 03/2019