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Current Sensing Switch, Normally Open Current Sensing Switch Adjustable AC 0.2-30A SZC23-NO-AL-CH

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$19.52

$ 8 .99 $8.99

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  • Self-powered, no external power supply required.Action current 0.2-30A AC, adjustable with a potentiometer.
  • LED indicator can conveniently and intuitively indicate the working status of the switch.Hysteresis is less than 1% and can be used under strong magnetic conditions.
  • The switch has no limit on the number of opening and closing, and the speed reaches the ms level.The outer casing is made of self-extinguishing material ABS.
  • High-power MOS tube contactless electronic switch.Straight-through structure design, isolation withstand voltage up to 2000V.
  • Suitable for AC current measurement and monitoring, AC motor overload , electronic switch of automatic control system and so on.


Product Description

AC current switch
current sensing switch

Good Choice

SZC23 series AC current sensing switch is designed and manufactured to solve the AC current monitoring. It uses the principle of mutual inductance to sense the AC straight-through current, isolate the AC current, and output a normally open or normally closed switching signal to directly control various automation industrial equipment, such as flash, buzzer, relay, single-chip or other power load equipment.

Compared with traditional mutual inductors, thermal protectors and other devices, using this device can not only get more accurate and more timely control, but can also greatly simplify the design and reduce costs.

Specification:

Model: SZC23-NO-AL-CH
Power supply: Not required
Rated load: ≤ 0.5A@240V AC/DC
Input current: 0.2-30A AC
Switch on minimum: 0.5±0.2A
Maximum overload: 100%
Leakage current: ≤0.1A
Accuracy: 1%
Hysteresis: ≤1%
Response time: ≤200ms
Repeatability: 100%
Working temperature: -20~60℃
Waterproof: IP30
Dimensions: 65×25×47mm / 2.56×0.98×1.85in
Hole diameter: 10mm / 0.4in
Package weight: Approx. 56g/2.0oz

Application Examples

Current Sensing Switch

Typical Wiring Diagram

Adjustable Current Sensing Switch

Combined with the contactor to indirectly control the AC and DC load

Current Sensing Switch

With PLC control AC motor

Normally Open Current Sensing Switch

Package list: Current Sensing Switch

Note:

  • 1. Due to the difference between monitors and light effects, the pictures may not reflect the actual color of the item.
  • 2. Please allow slight error due to manual measurement. Thanks for your understanding.

  • Based on electromagnetic induction, when the current in the circuit changes, an induced current is generated.
  • This series of AC current induction switch uses the inductance coil to induce the amplitude of the AC current to determine whether it exceeds the preset current action value to change the output state of a solid state switch, similar to the function of a mechanical switch.

The meaning of different indicators:

  • For NO normally open type, the green light indicates that the switch is off, current flows through the switch, but the starting value is not reached, and the contact is off;
  • The red light indicates that the switch is closed, the current reaches the starting value, and the contact is closed, the switch is in working condition.

Installation Instructions:

  1. Disconnect all power supplies in the circuit, and fix the AC current sensor switch in a proper position through the mounting hole of the base. If you use screws to install, make sure to tighten each screw.
  2. Connect the core current loop, first disconnect the tested circuit, let the tested circuit pass through the induction hole of the current switch, and reconnect the circuit; Connect the load circuit, note that the maximum AC load of this series of current switches cannot exceed 0.5A@240V AC/DC.
  3. After checking that the installation connection is correct, turn on the power switch and set the upper and lower limits of the induction switch current according to the user's needs: NO normally open type If the red light is on at this time, adjust the potentiometer to the H direction until the green light is on and stop, then adjust it to the L direction, and then stop when the red light is on. If the green light is on at this time, turn the adjustable potentiometer to the L direction until the red light just lights up and stop. The alternating point of the red and green lights is the current value of the current through the heart.

Common Problems and Solutions:

  1. After the penetration current reaches the set value, the load circuit is not automatically connected: Solution: Check whether the wiring of the output signal is loose and whether the load circuit wiring is loose. If an AC contactor is used, check whether the wiring of the AC contactor is loose and whether the AC contactor is damaged.
  2. After the AC feedthrough current is applied, the two LED indicators are off: Solution: Check whether the input AC current is normal and whether the wiring is loose.
  3. After the AC feedthrough current is applied, both LED indicators are on: Solution: The input AC feedthrough current is too large, pay attention to the feedthrough current not too large, if it exceeds the allowable range of the current sensor switch, the switch will be damaged.

Jeff F.
2025-07-27 09:26:44
This is my 3rd one. Using in a residential 24VDC PLC application. Solid so far
Joe
2025-07-21 16:35:42
I used this switch to turn a lamp on/off that was installed at the bottom of a staircase and powered on a separate circuit from the light at the top of the stairs. The switch operated by sensing the current in a traveler on a two-way switch at the bottom of the stairs (no neutral available there) and triggered a relay to handle the current needed for the lamp. The modified circuit works with approximately a one-second delay, which does not impact the ability to fully light the stairway for use.
T. Parolisi
2025-06-23 11:26:57
Use to turn on exhaust fan on dryer. Switch ac-ac solid state switch to insure handling of power.
William R. Reynolds
2025-05-16 15:21:17
Works great!
Festus
2025-05-09 12:02:27
when my sump pump turns on the red light comes on, which was what I wanted. I used the black wire as the trigger, I did 2 loops with it.
Jim Moore
2025-03-16 10:22:14
Easy to setup.
D R Wisdom
2025-03-14 11:53:41
Worked well and saved me $50 or so each
Jimmie Poage
2025-02-06 10:19:55
Bought this to turn on one amplifier when another was turned on. First it came with no wiring diagram or instructions, but it is a relatively simple device. However to the inexperienced, it could easily be connected wrong. Once I connected it up, it at first didn't work at all. Relay stayed in NOpen. Then it started working for 3-4 times, then stopped in the NClosed mode. No matter what I did, could not get it to "unstick". Even with no power at all connected. Returned and found another solution.
Customer
2025-02-05 16:32:30
As described
RobR
2025-01-21 17:35:26
Using it to shut down a secondary load when my air compressor turns on.