Safety relay module SRM 21 RT2

  • Enclosure width: 22.5 mm
  • 2 NC or 1 NC/1 NO contact can be connected
  • Feedback circuit
  • 2 enabling paths
  • 1 transistor output
  • Manual or automatic reset
  • LED indicator for switching condition
  • Crossed wire monitoring
  • N.B.: Please state required international approvals with your order!

Technical data

Applied standardsEN ISO 13849-1; EN 62061;
EN 60204-1, GS-ET-20;
EN 60947-5-1, -3; EN 61326-3-1
Enclosureblack polycarbonate
Contact materialSilver, gold flashed
MountingDIN rail mounting
Connectionscrew connection terminals with + and - screws
Cable cross-sectionmin. 1x 0.5 mm² (AWG 20) including conductor ferrules, max. 1x 2.5 mm² (AWG 14) including conductor ferrules, 2x 1.5 mm² (AWG 16) including conductor ferrules
Tightening torquescrew connection terminals: approx. 0.8 Nm
Degree of protectionenclosure IP 40, terminal block IP 20 to IEC/EN 60529, protection against contact to VBG 4
 
Safety-relevant data:
EN 62061SIL CL 3
PFHd3 x 10-8 1/h
Category4
TMmax. 20 years
MTTFd> 113 years
DC/DCavg> 99 %
 
Safety requirements nop
hop8 h/day
dop220 days/year
tzyklus30 s
EN 60204-1stop category 0
 
Rated operating voltage Ue24 VDC ±15 %
Rated operating current Ie0.125 A
Rated operating isolation voltage Ui250 VAC
Rated impulse withstand voltage Uimp4 kV
Conditional short-circuit current100 A
Inputs1 NC/1 NO contact or 2 NC contacts, 1 feedback circuit, 1 start input (monitored)
Outputs2 enabling paths, 1 transistor output as signalling output
Rated operating current/voltage Ie/Ueto EN 60947-5-1: 2 A/230 VAC; 1 A/24 VDC
to CSA: B300/R300, 250 VAC
Conventional thermal current Ithe5 A
Utilisation categoryAC-15; DC-13
Contact load capacitymin. 10 mA
Typ. input current/
voltage
22 mA / 20 VDC
Max. load of signalling output20 mA
Max. fuse ratingpower supply 2A slow blow, enabling paths 6 A gG/gN fuse
Delay on energisation/ deenergisation≤ 20 ms
Risk time≤ 0.5 s (switch-on delay)
Attendance delay tv< 200 ms
Mechanical life> 50 million operations
Display1 LED for supply voltage, 1 LED each for input A and B, 1 LED for authorisation
Degree of pollution2
Overvoltage categoryIII
Ambient temperature–22 °C … +55 °C
Storage and shipping temperature–22 °C … +70 °C
Relative humidity10 % ... 90 %
Shock resistance15 g
Approvals
on request
NoteInductive loads (contactors, relays etc.) are to be suppressed by suitable circuitry.
NoteThe safety-related data are based on a load of 24 V / 1 A / DC-1 for the enabling paths. With higher load currents for the enabling paths and other requirement rates nop, the safety-related data vary from the given data and can be provided on request.
Weight220 g

Ordering details

Type   Material no.  
Type    Material no.   
Safety relay module SRM 21 RT2 stock type Standard versions, in stock or available at short notice 1179203
If you cannot find the version you require, just ask us! Our product portfolio to date has included many customised switchgear variants.