Page top

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 voltage
12 to 24 VDC (Allowable voltage fluctuation range: 10 to 30 VDC)
0 to 1 MΩ variable
Note: 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.)
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
NPN open-collector transistor output with 100 mA at 30 VDC max. for both liquid leakage
detection and disconnection detection.
Note: If the rightmost pin of the DIP switch on the side of the Sensor Amplifier is set
to thedown 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.
Note: 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 ---
K7L-UD/UDB 1 1 1

* For the K7L-UD.