Safety relay module SRM 21 Multi

  • Enclosure width: 22.5 mm
  • 2 NC or 2 change-over contacts can be connected
  • Feedback circuit
  • 2 enabling paths potential-free
  • 1 auxiliary output
  • Manual or automatic start
  • LED indicator for switching condition
  • PL e, SIL CL 3

Technical data

Applied standardsEN ISO 13849-1, EN 62061,
EN 574, EN 60947-5-1
EnclosurePA66, self-extinguishing UL 94 V-0
Contact materialSilver, gold flashed
MountingDIN rail mounting
Connectionscrew connection terminals
Cable cross-section0.2 ... 1.5 mm² (incl. conductor ferrules)
Degree of protectionenclosure and terminals IP 20 to IEC 60529, protection against contact to VBG 4
Safety-relevant data:
EN 62061SIL CL 3
PFH2.15 x 10-9 1/h
EN ISO 13849-1Performance Level PL e
TMmax. 20 years
MTTFd100 years
DC/DCavg> 99 %
Rated operating voltage Ue24 VDC -20 % ... +25 %
Rated operating current Ie0.125 A
Rated operating isolation voltage Ui250 VAC
Rated impulse withstand voltage Uimp4 kV
Inputs2 NC inputs, 1 feedback circuit, 1 start input (monitored)
Outputs2 enabling paths, 1 transistor output as signalling output
Rated operating current/voltage Ie/Ueenabling paths: 3 A/230 VAC; 5 A/24 VDC
Utilisation categoryAC-15; DC-13
Contact load capacity5 mA … 6 A; 5 V ... 250 VAC/DC
Typ. input current8 mA
Typ. input voltage24 VDC
Max. load of
output circuits
50 mA (short-circuit proof)
Conditional short-circuit current1000 A
Short-circuit protectionsupply voltage: 2 A slow blow; enabling paths: 6,3 A qick-acting; 4 A slow blow
Delay on energisation/ deenergisation≤ 125 ms
Risk time≤ 0.5 s (switch-on delay)
Simultaneity of
input circuits
< 0.5 s with two-hand control circuit
Mechanical life> 10 million operations
Display2 LEDs for inputs, 2 LEDs for outputs, 1 LED for supply voltage, 1 LED for fault
Degree of pollution2
Overvoltage categoryIII
Ambient temperature–25 °C … +55 °C
Storage and shipping temperature–25 °C … +75 °C
Shock resistance10 g
ApprovalsTÜV Nord
NoteInductive loads (contactors, relays etc.) are to be suppressed by suitable circuitry.
Weight120 g

Ordering details

Type   Material no.  
Type    Material no.   
Safety relay module SRM 21 Multi stock type Standard versions, in stock or available at short notice 1185607
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