AUTOMATION
CONTROLS

Search
Discontinued
Products



Safety Control Unit SF-C21

Specifications

Product name Safety control unit
Model No. SF-C21
Applicable
standards
Safety IEC 61508-1 to 7, EN 61508-1 to 7(SIL3), ISO 13849-1 (Up to Category 4, PLe),
IEC 61131-2, IEC 61010-2-201, IEC 62061(SILCL3),
UL 61010-1, UL 61010-2-201, UL 1998,
KS C 9811 : 2019(EN 55011), KS C 9610-6-2 : 2019(EN 61000-6-2)
EMC IEC 61000-6-2, IEC 61326-3-1, EN 55011
Related standards IEC 60947-1, IEC 60947-5-1, IEC 60947-5-2, IEC 60947-5-5
IEC 60947-5-8, IEC 61496-1, IEC TS 62046, ISO 13851
Applicable regulations and certifications CE Marking (Machinery Directive, EMC Directive, RoHS Directive), UKCA Marking [Supply of Machinery (Safety)Regulations, EMC Regulations, RoHS Regulations], TÜV SÜD certification, TÜV SÜD NRTL certification, Korea's Radio Waves Act conformity registration
Supply
voltage
(Note 1, 2)
Power supply
for internal
24 V DC +10-15% Ripple P-P10 % or less
Power supply
for external
24 V DC +10-15% Ripple P-P10 % or less
Current
consumption
(Note 1, 2)
Power supply
for internal
200 mA or less
Power supply
for external
100 mA or less
Safety input (IN1 to IN8) 2×4 inputs, Rated voltage: Same as the voltage of the power supply for internal
  ON level /
OFF level
Input voltage: 18 V, Input current: 3.5 mA / Input voltage: 5 V, Input current: 1.0 mA
Rated input current /
Input impedance
5 mA approx. / 4.7 KΩ approx.
Duration of
detectable
ON state
10 ms or more
Duration of
undetectable
OFF state
0.7 ms or less
Control output
(OUT1 to OUT4)
PNP open-collector transistor with 2 outputs × 2
• Maximum source current: 300 mA / output
• Applied voltage: Same as the voltage of the power supply for external
• Residual voltage: 2.5 V or less
• Leakage current: 100 μA or less (Including power supply OFF condition)
  Output mode True : ON, False : OFF
ON delay function /
OFF delay function
Incorporated / Incorporated
Short-circuit
protection /
Response time
Incorporated / OFF response: 10 ms or less, ON response: 100 ms or less
Auxiliary output
(AUX1 to AUX4)
(Non-safety output)
PNP open-collector transistor with 1 output × 4
• Maximum source current: 60 mA / output
• Applied voltage: Same as the voltage of the power supply for external
• Residual voltage: 2.5 V or less
• Leakage current: 100 μA or less (Including power supply OFF condition)
  Output mode
(Factory defaults)
AUX1: Negative logic of OUT1 / OUT2 (ON when OUT1 / OUT2 is OFF)
AUX2: Negative logic of OUT3 / OUT4 (ON when OUT3 / OUT4 is OFF)
AUX3: Reset trigger output (ON under reset release wait condition)
AUX4: Lockout output (OFF when lockout)
Output mode
(Any of the
auxiliary outputs
can be customized
using the
software tool)
Negative logic of OUT1 / OUT2(ON when OUT1 / OUT2 is OFF)
Negative logic of OUT3 / OUT4 (ON when OUT3 / OUT4 is OFF)
Positive logic of OUT1 / OUT2 (ON when OUT1 / OUT2 is ON)
Positive logic of OUT3 / OUT4(ON when OUT3 / OUT4 is ON)
Outputs A, B, C, and D of diagnosis results of input blocks (ON when logic is true)
Outputs E, F, and G of internal logic circuit diagnostic results (ON when logic is true)
Reset trigger output (ON under reset release wait condition)
Lockout output (OFF when lockout)
Muting indicator output (ON when muting / override)
Monitor output in response to IN1 to IN8 (ON when input)
No output (normally OFF)
Short-circuit
protection /
Response time
Incorporated / 10 ms or less
Muting indicator output Semiconductor photo MOS relay output × 1
• Maximum load current: 60 mA
• Supply voltage: Same as the voltage of the power supply for internal
• Residual voltage: 2.5 V or less
• Leakage current: 100 μA or less (Including power supply OFF condition)
  Output mode ON when muting / override
Short-circuit
protection /
Response time
Incorporated / 10 ms or less
Interlock function /
Lockout release
function
Incorporated / Incorporated
External device
monitor function
Incorporated
Communication function
(MODBUS RTU)
Interface: RS-485
Protocol: MODBUS RTU
Maximum transmission distance: 100 m 328.084 ft
Maximum number of units that can be connected: 8 units (slaves)
Logic selection function No.0: Customization control
No.1: Overall stop control
No.2: Parallel muting control
No.3: Sequential muting control
No.4: Partial stop control 1
No.5: Partial stop control 2
No.6: Two-hand control
No.7: OR control
No.8: Operation mode selection control
Logic setting function Input mode, control mode, output mode, reset mode, auxiliary output mode
Pollution degree /
Excess voltage category
2 / II
Usable altitude (Note 3) 2,000 m 6561.680 ft or less
Startup time
after power on
2 sec. or less
PFHD(Note 4) / MTTFD (Note 4) 9.73 × 10−10 / 100 years or more
Protection IP20 (IEC) (must be installed in a control panel with protection IP54 or higher)
Ambient temperature -10 to +55 ℃ +14 to +131 ℉ (No dew condensation or icing allowed),
Storage: -25 to +60 ℃ -13 to +140 ℉
Ambient humidity 30 to 85% RH, Storage: 30 to 85% RH
Dielectric strength voltage
/ Insulation resistance
1,000 V AC for one min. / 20 MΩ, or more, with 500 V DC megger.
(All inputs connected together - USB port,
all inputs connected together - RS-485 port,
USB port - RS-485 port,
between all supply terminals connected together and enclosure,
all outputs connected together - all input connected together,
all outputs connected together - USB port,
all outputs connected together - RS-485 port)
Vibration resistance 5 to 8.4 Hz frequency, 3.5 mm 0.138 in half amplitude, 8.4 to 150 Hz frequency,
Max. acceleration 9.8 m/s2 (1 G), in X, Y and Z directions for two hours each
(IEC / EN 60068-2-6)
Shock resistance 147 m/s2 (15 G) 11 ms in X, Y and Z directions three times each (IEC / EN 60068-2-27)
Connection method Input / output and power supply: Detachable spring cage terminal blocks,
RS-485: Detachable spring-cage terminal block,
USB: Mini-B male
Maximum cable length 100 m 328.084 ft or less
Material Main unit enclosure: Polycarbonate / ABS polymer alloy,
Enclosure: Polycarbonate
Weight Net weight: 190 g approx., Gross weight: 320 g approx.

Notes:
1) "Power supply for internal" is the power supply for safety input. "Power supply for external" is the power supply for control output / auxiliary output. The power supplies for internal and external are insulated.
2) The power supply unit connected to this device must satisfy the conditions below.
• Output voltage within 20.4 V to 26.4 V DC (Ripple P-P: 10% or less.)
• Power supply unit SELV (safety extra low voltage) / PELV (protected extra low voltage) conforming to the EMC Directive and Low-voltage Directive (In case CE Marking conformity is required.)
• Power supply unit conforming to the Low-voltage Directive and with an output of 100 VA or less
• Power supply unit with an output holding time of 20 ms or more.
• Power supply unit SELV (safety extra low voltage) / PELV (protected extra low voltage) conforming to the EMC Regulations and Low-voltage Regulations (In case UKCA Marking conformity is required.)
• Power supply unit corresponding to CLASS 2 (In case C-TÜV US Listing Mark conformity is required.)
3) Do not use or store this device in a pressurized environment beyond the atmospheric pressure at sea level.
4) PFHD: Probability of dangerous failure per hour, MTTFD: Mean time to dangerous failure (in years)

RS-485 (MODBUS RTU) SPECIFICATIONS

With built-in RS-485, SF-C21 can read out its status, error history, etc. to an external device such as a general-purpose PLC, using the MODBUS RTU protocol.
Up to eight SF-C21 units can communicate with the external device as the master station.
The communication preference of MODBUS RTU is set with the DIP switch on the main unit or the software tool "Configurator SF-C".

Types of data that can be read out
• Status (HIGH, LOW) of safety input and reset / EDM output
• Status (HIGH, LOW) of control output, auxiliary output, and muting indicator output
• Lockout history
• Logic No. change history

■ MODBUS RTU SPECIFICATIONS

Interface RS-485
Max. transmission distance 100m 328.084 ft
Communication address 1-247
Data length 8 bits(fixed)
Parity bit Without / Odd / Even
Stop bit 1 bit / 2 bits
Communication speed 9,600 bps
19,200 bps
38,400 bps
57,600 bps
115,200 bps

■ MAIN BODY DIP SWITCH SPECIFICATIONS

Switch
NO.
Setting item Input status
OFF ON
1 Communication
preference settings
DIP switches take precedence Software tools take precedence
2 Parity bit presence With Without
3 Parity bit type Odd Even
4 Stop bit 1 2
5 Communication address 1 SW5:OFF, SW6:OFF
Communication address 2 SW5:ON, SW6:OFF
6 Communication address 3 SW5:OFF, SW6:ON
Communication address 4 SW5:ON, SW6:ON
7 Communication speed 9,600 bps 19,200 bps
8 Reserved - -
9 Reserved - -
10 Reserved - -

Note: The SF-C21 cannot be controlled by an external device.

Return to top

CONTACT US
If you have any questions, please select the option below to contact us or find answers.
CONTACT BY EMAIL / PHONE FIND LOCAL OFFICE

Return to top

CONTACT US
BY EMAIL
Please click your area to select country or region







BY PHONE

Requests to customers (Automation Control Components & Industrial Device) [Excluding specific product]
Requests to customers (Automation Control Components & Industrial Device) [For specific product]
Requests to customers (FA Sensors & Components [Excluding motors])
Requests to customers (Dedicated to industrial motors)