Notes Switch travel diagram
  Contact closed
  Contact open
  Setting range
  Break point
  Positive opening sequence/- angle
VS  adjustable range of NO contact
  adjustable range of NC contact
N   after travel
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• Multifunctional safety relay module for superior diagnostics and visualisation
• Suitable for signal processing of potential-free outputs, e.g. emergency stop command devices, position switches and solenoid interlocks
• Suitable for signal processing of outputs connected to potentials (AOPDs), e.g. safety light grids/curtains
• Fit for signal evaluation of outputs of safety magnetic switches
• 3 safety contacts, STOP 0
• 2 + 6 Signalling outputs
• Level 1: Reset without edge detection, Optional Automatic reset function, Short-circuit recognition, Level 2: / Opener (NC) Normally open contact (NO)

Ordering details
Product type descriptionSRB308IT-230VAC
Article number101158202
EAN Code4250116201563
Replaced article number 101166107
Approval USA/CAN
StandardsEN ISO 13849-1, IEC 61508, EN 60947-5-1
PLup e ( STOP 0)
Control categoryup 4 (STOP 0)
DC99% (STOP 0)
CCF> 65 points
PFH value≤ 2,0 x 10-8/h (STOP 0)
SILup 3 (STOP 0)
Mission time20 Years
- noticeThe PFH value is applicable for the combinations listed in the table for contact load (K) (current through enabling paths) and switching cycle number (n-op/y).
In case of 365 operating days per year and a 24-hour operation, this results in the specified switching cycle times (t-cycle) for the relay contacts.
Diverging applications on request.
Global Properties
Permanent lightSRB308IT
StandardsIEC/EN 60204-1, EN 60947-5-1, EN ISO 13849-1, IEC 61508
Compliance with the Directives (Y/N) Yes
Climatic stressEN 60068-2-78
Mountingsnaps onto standard DIN rail to EN 60715
Terminal designationsIEC/EN 60947-1
- Material of the housingsPlastic, glass-fibre reinforced thermoplastic, ventilated
- Material of the contactsAgSn0, Ag-Ni, self-cleaning, positive action
Start conditionsAutomatic or Start button ( Optional monitored)
Start input (Y/N)Yes
Feedback circuit (Y/N)Yes
Start-up test (Y/N)No
Automatic reset function (Y/N)Yes
Reset with edge detection (Y/N)Yes
Pull-in delay
- ON delay with automatic starttyp. 60 ms
- ON delay with reset buttontyp. 200 ms
Drop-out delay
- Drop-out delay in case of emergency stop≤ 15
Mechanical data
Connection typeScrew connection
Cable section
- Min. Cable section0,25
- Max. Cable section2.5
Pre-wired cablerigid or flexible
Tightening torque for the terminals0,6
Detachable terminals (Y/N)Yes
Mechanical life10.000.000 operations
Electrical lifetimeDerating curve available on request
restistance to shock30 g / 11 ms
Resistance to vibration To EN 60068-2-610…55 HZ, Amplitude 0,35 mm
Ambient conditions
Ambient temperature
- Min. environmental temperature−25
- Max. environmental temperature+45
Storage and transport temperature
- Min. Storage and transport temperature−40
- Max. Storage and transport temperature+85
Protection class
- Protection class-EnclosureIP40
- Protection class-TerminalsIP20
- Protection class-ClearanceIP54
Air clearances and creepage distances To IEC/EN 60664-1
- Rated impulse withstand voltage Uimp4 kV
- Overvoltage categoryIII To VDE 0110
- Degree of pollution2 To VDE 0110
Electromagnetic compatibility (EMC)
EMC ratingconforming to EMC Directive
Electrical data
Rated DC voltage for controls
- Max. rated DC voltage for controls-
- Max. rated DC voltage for controls-
Rated AC voltage for controls, 50 Hz
- Min. rated AC voltage for controls, 50 Hz215
- Max. rated AC voltage for controls, 50 Hz253
Rated AC voltage for controls, 60 Hz
- Min. rated AC voltage for controls, 60 Hz215
- Max. rated AC voltage for controls, 60 Hz253
Contact resistancemax. 100 mΩ
Power consumption3 W; 3 VA
Type of actuationAC
Rated operating voltage Ue230 VAC −15% / +10%
Operating current Ie0,125 A
Frequency range50 / 60
Electronic protection (Y/N)Yes
Fuse rating for the operating voltageInternal electronic trip, tripping current > 0,5 A,
Reset after disconnection of supply voltage
Current and tension on control circuits28 VDC / 50 mA
Current and tension on control circuits
- S11, S12, S21, S22, S31, S32max. 28 VDC, Test current: 50 mA
- X3 … X5max. 28 VDC, Test current: 100 mA
Monitored inputs
- Short-circuit recognition (Y/N)optional
- Wire breakage detection (Y/N)Yes
- Earth connection detection (Y/N)Yes
Number of shutters0
Number of openers2
Cable length1500 m with 1.5 mm²;
2500 m with 2.5 mm²
Conduction resistancemax. 40 Ω
- Stop category 0Residual current at ambient temperature up to: - 45°C = 18 A; - 55°C = 15 A; - 60°C = 12 A
- Stop category 1Residual current at ambient temperature up to: - 45°C = 12 A; - 55°C = 10 A; - 60°C = 8 A
Stop category0
Number of safety contacts3
Number of auxiliary contacts2
Number of signalling outputs6
Switching capacity
- Switching capacity of the safety contactsmax. 250 VAC, 6 A ohmic (inductive in case of appropriate protective wiring)
min. 10 V / 10 mA
- Switching capacity of the auxiliary contacts24 VDC, 2 A
- Switching capacity of the signaling/diagnostic outputs24 VDC, 10 mA
Fuse rating
- Protection of the safety contacts6.3 A slow blow
- Fuse rating for the auxiliary contacts2 A slow blow
- Fuse rating for the signaling/diagnostic outputsInternal electronic trip, tripping current > 0,1 A
Utilisation category To EN 60947-5-1AC-15: 230 V / 1,5 A
DC-13: 24 V / 1,2 A
Note on the utilisation category
Number of undelayed semi-conductor outputs with signaling function6
Number of undelayed outputs with signaling function (with contact)2
Number of delayed semi-conductor outputs with signaling function.0
Number of delayed outputs with signalling function (with contact).0
Number of secure undelayed semi-conductor outputs with signaling function0
Number of secure, undelayed outputs with signaling function, with contact.3
Number of secure, delayed semi-conductor outputs with signaling function0
Number of secure, delayed outputs with signaling function (with contact).0
LED switching conditions display
LED switching conditions display (Y/N)Yes
Number of LED´s5
LED switching conditions display
- The integrated LEDs indicate the following operating states.
- Position relay K1
- Position relay K3
- Position relay K2
- Supply voltage
- Internal operating voltage Ui
Miscellaneous data
Applications Guard system
Emergency-Stop button
Pull-wire emergency stop switches
Safety sensor
Safety light curtain
- Width45 mm
- Height100 mm
- Depth121 mm
Inductive loads (e.g. contactors, relays, etc.) are to be suppressed by means of a suitable circuit.
notice - Wiring example
2 channel control shown for a guard-door monitor with two contacts, of which at least one contact has positive break, with external reset button (R) and feedback circuit (H2). (example without cross-wire monitoring)
The control recognises cross-short, cable break and earth leakages in the monitoring circuit.
Relay outputs: Suitable for 2 channel control, for increase in capacity or number of contacts by means of contactors or relays with positive-guided contacts.
F1 = hybrid fuse
F2 = Fuse for signalling outputs
For 2-channel control with cross-wire monitoring, connect the NC contact to S11/S12 and S31/S32 and bridge S21/S22
For 1-channel control, connect NC contact to S11/S12 and bridge S21/S22 und S31/S32
Start function / Reset button:
The function "trailing edge" is programmed by means of the "AF" switch located underneath the housing cover (switch position = 1).
The automatic start is programmed by bridging terminals X3/X5 and by switching the "AF" switch to 0. The time offset between the channels is approx. 100 ms. An endless time offset between the channels 1 and 2 is programmed by bridging the terminals X3/X6.
Connect potential p-type outputs of safety light grids/curtains to S12/S22. The devices must have the same reference potential.
The ISD tables (Intergral System Diagnostics) for analysis of the fault indications and their causes are shown in the appendix.
The wiring diagram is shown with guard doors closed and in de-energised condition.

K.A. Schmersal GmbH & Co. KG, Möddinghofe 30, D-42279 Wuppertal
The data and values have been checked throroughly. Technical modifications and errors excepted.
Generiert am 20.09.2019 - 00:35:32h Kasbase 3.3.0.F.64I