SM 302 safety relay

As the most important part of safety loop, safety controller/safety PLC has been recognized by more and more people, but in the process of use, there are still many users who are confused about the differences between safety relay and ordinary relay, so I would like to share them with you here. As we all know, we must remember three words in the concept of safety design:

(1) Redundancy

(2) Difference

(3) Self-detection

How to construct the safety loop with the reliability above PLd, the safety controller must become an important link. The safety loop consists of safety input, safety control and safety output subsystems, and the safety control "including safety relay, safety controller, safety PLC, etc." realizes the safety control function. Designers match different safety controllers to achieve the reliability level of the safety loop according to the number of products at the input end.

▊ SM-302 programmable safety controller

· Is a configurable safety controller, which supports the input of various safety product components.

·Maximum support for 3 sets of dual-loop inputs.

·Iso 13849-1 performance index PLe

·Built-in self-diagnosis function for fault detection

·Modbus protocol communication

·Input and output fault indicator light

·Safety certification: PL e, Cat: 4

▊	Product selection

product name

model

Safety input

Safe output

brand

Programmable safety controller

SM-302

3CH

2NO

LHS

explain

Up to 3 sets of dual-channel security products can be entered.

The programming software defines the field safety products by itself.

Official website programming software download connection.：http://lhsafety.com.cn/showinfo-257-118-0.html

▊	safety performance

·Performance level (PL): PLE

·Safety category (cat.): cat.4.

·Task time (TM): 20 years.

·Diagnostic coverage (DC/DC AVG): 99%

·Safety integrity level (SIL): SIL3

·Hardware fault margin (HFT): 1

·Safety Failure Score (SFF): 99%

·PFHD: 1.78e-9/h

·Stop category: 0/1

Comply with the standard EN ISO13849

Comply with standards IEC61508, IEC62061.

Comply with standard EN 60204-1.

▊	Main technical parameters

Power supply characteristics	·Power supply voltage: 24VDC ·Voltage range: 20~30VDC ·Current loss: ≤100mA(24VDC)
Input characteristics	·Input current: ≤10mA(24VDC) ·Conductor resistance: ≤15Ω ·Input equipment: emergency stop button, safety door, two-hand button, ·Safety light curtain, magnetic switch, etc ·Input channel: 3
output characteristic	·Number of contacts: 2NO (safety output) ·Contact material: AgSnO2 ·Contact fuse protection: 10A is fast, 6A is slow. ·Switching capacity: 5A/230VAC；; 5A/24VDC
Time characteristic	·Suction buffer time：≤100ms ·Release buffer time：≤30ms ·Recovery time: Emergency stop operation：≤30ms Power failure：≤1000ms ·Recovery time: Emergency stop operation：≤30ms Power failure：≤100ms ·Short-term interruption of power supply：20ms
Communication characteristics	·Baud rate: 38.4kbps (fixed) ·Communication length: ≤1000m ·Networking capacity: ≤10 units