Product Category

Liquid Leakage Sensor Amplifiers for Long-distance Wiring

K7L-U[] / UD[][]

Ultra-miniature Liquid Leakage Sensor Amplifier Enables Longest Liquid Leakage Monitoring Distance in Industry. K7L-UB and K7L-UDB are our Value Design products which increase the value of your control panels.


Ambient temperature

Operating: -10 to 55°C

Ambient humidity

Operating: 45% to 85%

Insulation resistance

10 MΩ at 100 VDC between case and current-carrying parts

Dielectric strength

1,000 VAC at 50/60 Hz for 1 min between case and current-carrying parts

Power consumption

1 W max.

Response time

Operate: 800 ms max.
 Release: 800 ms max.
 Startup time after power ON: 2 s max.


Approx. 14 g


Rated power supply

12 to 24 VDC (Allowable voltage fluctuation range: 10 to 30 VDC)

Operate resistance

0 to 1 MΩ variable
 The adjuster (ADJUST) on the top of the Sensor Amplifier sets the resistance for detection
 within the setting range. It is factory-set to the upper limit. (Normally, the K7L can be used with
 the adjuster at this setting.)

 detection function

Detection signal: 10 VDC max., 200 ms
 Detection time: 10 s max.
 Recovery: Operation is recovered by resetting the power supply.

Release resistance

105% min. of operate resistance


Open-collector transistor output with 100 mA at 30 VDC max. for both liquid leakage detection
 and disconnection detection.
 If the rightmost pin of the DIP switch on the side of the Sensor Amplifier is set to the down
 position, the output turns ON when liquid is detected; if it is set to the up position, the output
 turns OFF when liquid is detected.

Vibration resistance

10 to 150 Hz, 0.1-mm single amplitude with 15-m/s2 acceleration for 8 minutes 10 times each
 in X, Y, and Z directions

Shock resistance

150 m/s2 3 times each in six directions on 3 axes

Wiring distance

Wiring cable, Sensing Band: Total: 400 m max.
 These values are possible on the condition that a completely insulated 3-conductor VCT cable
with a thickness of 0.75 mm2 and a dielectric strength of 600 V is used together with the Liquid
Sensing Band specified by OMRON. (A 0.2-mm2 cable can also be used.)


Product Name

Terminal Block

Screwdriver for ADJUST














* For the K7L-UD[][].