I am in need of a simple computer controlled (through USB) device that will either open a relay for a specific amount of time (3-4 seconds) or power something on and off (i.e., a timed relay board requiring 5 or 12 volts) for a specified period of time (5-10 seconds during which the relay opens and then closes for 3-4 seconds). The device will be used to power up a piece of equipment that simply requires the opening and closing of a relay for 3-4 seconds in order to boot up the equipment. No power is to be fed by the device through the system to the equipment being booted, simply an open/close signal. The specific requirements are:
- The device should be both operated and powered through the USB port.
- No power is supplied through the system, simply an open/closed relay.
- In the second option the device being powered is a small timed relay board which needs power long enough to go through it’s 3-4 second open/close operation.
- In the second option the power supplied by USB port itself.
Our current system works just fine when using a Ethernet controlled AC power strip simply by turning an outlet on and off which then supplies the current timed relay board 12 volts for the necessary amount of time. Our problem is that we want to be able to send the relay signal without the use of the remote AC power strip with power instead being supplied by the USB port itself if at all possible. If necessary, we can power everything with a DC power supply though.
The first option would be ideal since it would eliminate the need for the second timed relay board. But either method will suffice.
Were it possible, this could all be accomplished through the timed powering on and off of a USB port but because that is generally not a possibility (either on a PC or a USB hub), this work around is needed.
One problem I have is that I don’t have any experience programming such a device so the programming cannot be too complicated but for this purpose I don’t think it should be. For the second option, one way that this could probably be accomplished is through a computer-controlled device that powers a DC motor on and off for the specified time which in turn would supply the 5-12 volts need to active the timed relay rather than powering a motor on/off.
Any suggestions on how to accomplish this would be appreciated.