GHM Martens GS125L User manual

Operating Manual
Limit switch
GS125L
EN
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Limit switch GS125
Table of contents
Intended use (areas of application).................................................................................................1
Safety signs and symbols ...................................................................................................................1
Safety instructions...............................................................................................................................2
Product liability and warranty..............................................................................................................2
Standards and directives.....................................................................................................................2
Product description ..........................................................................................................................3
Scope of Delivery................................................................................................................................3
Functional principle .............................................................................................................................3
Layout of the measuring system.........................................................................................................5
Block circuit diagram...........................................................................................................................6
Type label............................................................................................................................................7
Power Rail...........................................................................................................................................8
Assembly and installation................................................................................................................9
Mechanical assembly..........................................................................................................................9
Electrical Installation ...........................................................................................................................9
Connection Diagram .........................................................................................................................10
Limit contacts ....................................................................................................................................11
Positioning of individual scale marking .............................................................................................12
Operating steps, functional description, output..........................................................................13
Control elements, functional description...........................................................................................13
Commissioning, Maintenance and Service..................................................................................14
Commissioning..................................................................................................................................14
Maintenance......................................................................................................................................14
Service ..............................................................................................................................................14
Error and System Messages.............................................................................................................15
Technical Data.................................................................................................................................16
Safety-related key values..................................................................................................................18
Mechanical design / dimensions.......................................................................................................19
Accessories and replacement .......................................................................................................19
Order Code.......................................................................................................................................19
Device transport and storage ........................................................................................................20
Returns.............................................................................................................................................20
Disposal ...........................................................................................................................................20
Service..............................................................................................................................................21
Manufacturer.....................................................................................................................................21
Repairs processing ...........................................................................................................................21
Certificate of Conformity................................................................................................................22

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Limit switch GS125
Intended use (areas of application)
Refer to the chapter 2 Product description for detailed specifications for the area of application. The operational
safety of the device is only assured when used as intended in accordance with the specifications in the operating
manual. Intervention beyond the actions described in the operating manual may only be carried out by personnel
authorised by the manufacturer for safety and warranty reasons.
Conversions or modifications made on one's own authority are expressly prohibited.
Application-specific dangers can emanate from this device when used improperly or not as intended.
The device is not intended for use in explosion-prone areas.
General safety instructions, use
This operating manual must be kept in a location such that qualified personnel can refer to it at all times. Any
processes described in this operating manual may only be carried out by trained, qualified personnel
who are authorised by the owner and wearing protective clothing. All rights reserved.
Safety signs and symbols
Warning notices are identified in this document as described under Table 1:
Table 1 Safety sings and symbols
Danger
Warning! This symbol warns of imminent danger which can result in death, severe bodily
injury, or severe property damage in case of non-observance.
Attention! This symbol warns of potential dangers or harmful situations which can cause
damage to the device or to the environment in case of non-observance.
Note! This symbol indicates processes which can have a direct influence on operation or can
trigger an unforeseen reaction in case of non-observance.

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Limit switch GS125
Safety instructions
Read the product description before commissioning the device. Ensure that there are no limitations for use of
the product for the relevant applications. The owner is responsible for ensuring the fault-free operation of the
device. The owner is obligated to ensure compliance and to observe the required work and safety measures of
the current applicable regulations for the entire duration of use
Product liability and warranty
Exclusion of liability:
The contents of the operating manual have been checked to ensure conformity with the described device.
However, deviations cannot be entirely ruled out. Therefore, we cannot assume any guarantee for complete
conformity. The specifications in this document are checked regularly and any necessary corrections are
incorporated into subsequent versions. This document is subject to technical changes. In addition, all
claims are based on the valid 'Standard Terms for the Supply of Products and Services of the Electrical Industry'
GHM Messtechnik cannot inspect or repair any devices without the required form having been filled in
completely (see 10 Returns).
Standards and directives
Conformity with Directive 2014/30/EU
CE Conformity EN 61326-1:2013.
Conformity with Directive 2014/35/EU
Insulation coordinates EN 60664-1:2007
Functional safety
Testing standard EN 61508-1:2010
(Issue years for testing standards belong to german versions)
Danger

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Limit switch GS125
Product description
Limit switches of theseries GS125 are used inswitch cabinets for processmonitoring or even forsimple process
regulation. Temperatures and derived signals such as voltage, current and resistance can be used as control
signals. In the process, 1 or 2 limit values can be monitored. With the universal configurability of the measuring
inputs, the need to stock multiple parts for various applications is reduced. The housing width of only 12.5mm
allows space-saving installation in the switch cabinet. The limit value adjustment scales which are illuminated
red or green depending on the switching status also enable operation in dark environments
Scope of Delivery
- GS125, according to order code
- 24 transparent labels with measuring units and scale assignment
- Power Rail DIN rail adapter (only with LP version)
- these operating instructions
- if necessary, further documents
Functional principle
One or two relays may be switched depending on the measurement at the device input. Limit values can be
adjusted with illuminated adjustment wheels.When the limit values are reached (depending on the input signal),
relays are switched. The relay status is indicated by a colour change in the scales of the adjustment wheels.
The switching behaviour of the relay can be specified as a minimum or maximum contact. Device configuration
will be done via DIP switches. The relay is designed as a changeover contact for single-channel devices. Two-
channel devices can be optionally supplied with a universal connection of the relay contacts or with two potential-
free NO contacts. The universal connection enables use of the device with 2 independent NO contacts or in
window range monitoring in which the two contact relays can be open or closed within the target range. The
application is selected with the wiring of the outer connection terminals. A device version is available with
analogue output that reproduces the respective input signal to 4-20mA. The analogue output is not galvanically
isolated from the input signal! The device may be supplied in a wide range between 20..125V DC or 20..253V
AC. A low cost version with 24V DC power supply is available. Another version allows a 24V power supply via
a mounting rail bus (Power Rail) Twenty-four transparent adhesive labels are provided for assigning the unit of
measure for the scale labelling. They can be affixed between the adjustment wheels on the front panel,
depending on requirements.

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Limit switch GS125
Measuring ranges
Table 2 Measuring ranges
Input type
Factory range
Standard signal
Standard signal, live-zero
0…20 mA / 0…10 V
4…20 mA / 2…10 V
Potentiometer
1 kΩ…10 kΩ, nom
Pt100
-50 .. 50 °C
0 .. 50 °C
0 .. 100 °C
0 .. 150 °C
0 .. 200 °C
0 .. 300 °C
0 .. 500 °C
Thermocouple
Type J FeCuNi 0…250 °C
Type J FeCuNi 0…500 °C
Type K NiCrNi 0…500 °C
Type K NiCrNi 0…750 °C
Type K NiCrNi 0…1000 °C
Type S PtRhPt 0…1500 °C

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Limit switch GS125
Layout of the measuring system
Figure 1 Limit switch GS125
①
Terminals for auxiliary voltage
②
Terminals for relay
③
Terminals for relay
④
Type plate
⑤
Scale wheel, limit value A1
⑥
Scale wheel, limit value A2*
⑦
DIP-switches for configuration of
the input and the limit functions
A1, A2
⑧
Terminals for signal input
⑨
Terminals for analogue output
*available in device types with two limits, only.

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Limit switch GS125
Block circuit diagram
Relay as a changeover contact
Figure 2 Block circuit diagrams
2 Relay contacts with universal
circuit
2 potential-free contacts, NO

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Limit switch GS125
Type label
The type plate contains the most important identification data:
- Manufacturer
- Type and article description
- Technical specifications
- Serial number / barcode
Figure 3 Type Plate

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Limit switch GS125
Figure 4 Example: GS125LP with DIN rail connector and supply terminal PRVK
(optional accessories)
Figure 5 Terminal Assignment PRVK
Power Rail
The supply of multiple devices can be combined and simplified via a bus system in the carrier rail (TS35). A
corresponding version is available for the entire LP series of GHM carrier rail devices in a housing with 12.5 mm
width.
A bus adapter compatible with series connection is clamped on the carrier rail before installation of the device
to be supplied with power.
An adapter is required for each device. The bus power supply is provided via a plug-type terminal strip.
The power supply terminals 11 and 12 on the upper device side are omitted in device version GS125LP
designed for this purpose.