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K7L-U[] / UD[][]

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.
Weight 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.)
Accessories Product Name Terminal Block Screwdriver for ADJUST Terminator
Model F03-20 --- F03-20T
K7L-U/UB 1 1 ---

* For the K7L-UD[][].