Safety Barriers

I. Overview

The LU-BK22 safety barrier controls field devices in the hazardous area through switch, transistor or logic level signal input from the power supply in the safe area. It is suitable for driving intrinsically safe devices such as solenoid valves and alarms, as well as other simple devices without energy storage.

Powered by an independent DC power supply, with isolation between power supply, input and output.

With high/low level status indicator lamps for the output signal

Compact unit, light weight, suitable for high-density installation

II. Technical specifications

Input parameters (safe area signals)

Input type   

A.  Dry contact switch selected: input current  ≤3mA / 24V; switch delay ≤2s

B.  Level signal selected: high level 4~24V; low level ≤1V

C.  Transistor selected: electrical rating  30VDC, 100mA

Output parameters (hazardous area signals)

Output signal:  logic voltage signal

Output equivalent circuit (Figure 1):

Output characteristic curve (Figure 2):

Minimum output voltage: 12V at 45mA

Maximum output voltage: 24V

Maximum output current: 45mA

Input/output characteristics

Normal phase (*Note: the description in brackets refers to reverse phase)

A. Dry contact switch selected: if the input switch is closed, the output conducts and the output indicator yellow lamp lights up

B. Level signal selected: if the input high level is 4~24V, the output conducts and the output indicator yellow lamp lights up.

C. Transistor selected: if the input transistor is conducting, the output conducts and the output indicator yellow lamp lights up.

 In reverse phase, it does not conduct and the output indicator yellow lamp goes out)

A. If the input switch is open, the output does not conduct and the output indicator yellow lamp is off

B. If the input low level is <1V, the output does not conduct and the output indicator yellow lamp is off.

C. If the input transistor is not conducting, the output does not conduct and the output indicator yellow lamp is off.

 (In reverse phase, it conducts and the output indicator yellow lamp lights up)

Note: if reverse phase is required, it must be set via the internal micro switch of the product; please specify when ordering.

Intrinsic safety parameters

Explosion-proof marking: [Exia] ⅡC

  Maximum permissible voltage Um: 250V

  Maximum open-circuit voltage Uo: 25V

Maximum short-circuit current Io: 147mA

Maximum external inductance Lo: 1.4mH

Maximum external capacitance Co: 0.08μF

Ambient parameters

Power sup ply: DC24V±10%

Power indicator lamp: green LED, lit when the power is supplied

Current consumption (with 24VDC power supply): dual channel < 110mA (at output current 45mA)

Operating temperature: 0~ +50 °C

Storage temperature: -20~ +60°C

Relative humidity: 0 ~ 95%RH (non-condensing)

General technical parameters

Standard accuracy: ±0.1%

Temperature drift: ±0.015%/°C

Response time: ≤10mS

Insulation resistance: 2.5KV, 1min, 50HZ between input, output and power supply

Isolation strength: input-output-power supply ≥100MΩ/500VDC

Power-on stabilization time: ≤3s