I am new to the webpage and to electronics so please bear with me if my question seems too basic. I bought an electromagnetic lock for my fence. the data sheet for the lock says it works w 12V DC @ 110 mA and it comes with only a negative and a positive wire attached to the main body of the magnet. I have an electric gate (mighty mule 200) operated with a remote clicker; the circuit board of the gate has a Lock+ pin that allows the EM lock to be connected via a logic circuit which I tried to design.
The gate will send 0 volts normally through the lock+ pin and when I activate the gate to open, it will send +13V for 1-2 seconds before going back to 0V.
I decided to use a PNP 3906 transistor as depicted in the diagram to signal the lock when the gate is being activated. The 3906 acts as a normally closed switch allowing current from Emisor to Collector and keeping the lock activated. When the gate is opened, +13V go to the Base and transiently opens the circuit; the lock deactivates and the gate is allowed to swing open.
The circuit seems to be working as expected in terms of the logic, but the force of the electromagnet is very weak when I hook it up. When I measure the current from A-B in the diagram, I get 50mA which I think is the reason why the magnet is not working at full capacity... Do you have any ideas on how to increase the current that goes to the magnet? from the spec sheet it can stand up to 110 mA.
The gate will send 0 volts normally through the lock+ pin and when I activate the gate to open, it will send +13V for 1-2 seconds before going back to 0V.
I decided to use a PNP 3906 transistor as depicted in the diagram to signal the lock when the gate is being activated. The 3906 acts as a normally closed switch allowing current from Emisor to Collector and keeping the lock activated. When the gate is opened, +13V go to the Base and transiently opens the circuit; the lock deactivates and the gate is allowed to swing open.
The circuit seems to be working as expected in terms of the logic, but the force of the electromagnet is very weak when I hook it up. When I measure the current from A-B in the diagram, I get 50mA which I think is the reason why the magnet is not working at full capacity... Do you have any ideas on how to increase the current that goes to the magnet? from the spec sheet it can stand up to 110 mA.
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