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Threshold Voltage Switch Kit

Threshold Voltage Switch Kit

  • CAT.NO: KC5528

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Threshold Voltage Switch Kit
Refer: Silicon Chip Magazine July 2014
A simple but versatile device to switch a relay when its input voltage crosses a threshold. Use it to prevent a lead-acid battery from being over-charged or in automotive applications to trigger an extra fuel pump under high boost, anti-lag waste-gate shutoff for example. A PCB mount 12V DPDT relay is supplied but the circuit caters for other types depending on the voltage and current you want to switch. In conjunction with a standard battery charger and suitable resistor, the device can also be used to trickle charge a lead-acid battery.

- 5 - 24VDC operation
- Adjustable trigger threshold
- Trigger on high or low voltage
- Output state indicator LEDs
- Multiple relay options (Kit supplied with onboard relay)

Kit supplied short-form with double sided, solder-masked and screen-printed PCB, onboard relay and electronic components. Cabling and case not included. PCB size: 107 x 61mm

Optional relays:
24V 12V DPDT PCB Relay: SY-4053
30A 12V SPST Horn Relay: SY-4040
30A 12V SPDT Horn Relay: SY-4070
60A 12V SPDT Horn Relay: SY-4074

Kit Form

Short Form (circuit only)



Instructions Included


Additional optional items

Higher capacity relay: SY-4053, SY-4040, SY-4070, SY-4074

Kit Group

General Projects

Product Dimensions


107 mm


61 mm

Packaged Dimensions

Packaged Volume

0.6 l

Packaged Weight

0.122 kg

Packaged Qty

1 pc

Packaged Type

Blister Pack - Single

Packaged Length

20 cm

Packaged Width

10 cm

Packaged Height

3 cm

Shipping Volume

0.68053 l