Not because GPS tracking system How to use the relay for GPS tracking system in vehicles

Not because GPS tracking system How to use the relay for GPS tracking system in vehicles

12v/24v relays are widely used in automobiles. Also, they are very useful in GPS tracking systems. In most cases, relays are connected to a GPS tracking system to control the car engine on or off. Actually, the relay makes the engine off/on only when the engine is started by the driver, if the engine is not started by the driver, the relay is not able to turn the engine on, kindly note it.

Take the 12v relay as an example, it has two circuits inside, one is 87a(or 87)—30 which is integrated into the auto engine circuit; the other is 85—86 which is integrated into the GPS tracker circuit. But in a word, the engine circuit and GPS tracker device circuit belong to the 12v car circuit which is a bigger system including much more electronics like car doors, etc. The two circuits are connected independently in some extent. They almost meet at an extremely small place: relay.

There is a switch and a copper wire coil inside the relay. If the relay not working or the 87a—30 circuit is in state, the switch is attached to the 87a. and no current through the copper wire coil if no current through 87a—30. There are two ways to connect GPS trackers to relay: one is GPS tracker —87a—30, the other is GPS tracker—-87—30.

For 87a—30, it’s: GPS positive + ——- 87a——30— GPS negative – . The GPS positive is the same as the positive of power cables, the GPS negative is the digital output cable. The output cable is disconnected to the ground if you don’t send a command to turn it on. When you send a command to the GPS tracker by SMS or GPRS, the output cable is connected to the ground, which leads to the circuit of 87a—30 is on, and the current makes the copper coil generate magnetic power. The magnetic power attracts the switch to itself. Thus it breaks the 85-86 circuit which stands for the engine circuit.

For 87-30, it’s GPS positive + ——- 87——30—— GPS negative -. The GPS positive is the same as the positive of power cables, the GPS negative is the digital output cable. The output cable is disconnected to the ground if you don’t send a command to turn

it on. When you send a command to the GPS tracker by SMS or GPRS, the output cable is connected to the ground, which leads to the circuit of 87—30, and the current makes the copper coil generate magnetic power. The magnetic power attracts the switch to itself. The difference between the two circuits is: the switch status. For the former, the engine works if the switch is with 87a; for the latter, the engine works if the switch is with 87. It means if you want to start the engine with 87-30, you should make the switch attaching to 87.

This generates another good result: if somebody takes away the GSP tracker from the car circuit, the car engine circuit is cut also because the switch would be back to 87a automatically if the magnetic power disappears.

If a driver wants to start the engine, the 87—30 circuits should be on,
You may check this video below for an understanding of how the relay functions internally in a GPS tracking solution. Or you can check the video on YouTube.