desperado1
Full Member level 3
I have a 24VDC supply, and the ability to provide several 5VDC (20 mA) signals.
I need to operate 25 devices (one at a time, randomly selected). Each device is 24V, 1A.
The easiest way to do this would be to have 25 relays (each controlled by the 5VDC signal). However, is there a better way of doing this? Is there a way that is (A) cheaper and (B) uses fewer of those 5VDC signals?
I know that if you have 5 bits of information, you can have 2^5 = 32 conditions. But is it possible to operate devics with just 5 on/off relays?
I can easilly picture a grid, with five switches forming rows and five switches forming columns. Then have an AND gate at each intersection. If the row AND column are turned on, then that lightbulb turns on. That gives just 10 relays needed. Is there a better way though? Also, are there AND gates available that operate at 24V and 1A?
Or is there any rotary switch that can handle 24V at 1A and is controlled by a 5VDC signal? I could use this to move from device to device. Then use one relay to turn on/off the power so that only the desired device is operating as the rotary switch moves to the next device.
I need to operate 25 devices (one at a time, randomly selected). Each device is 24V, 1A.
The easiest way to do this would be to have 25 relays (each controlled by the 5VDC signal). However, is there a better way of doing this? Is there a way that is (A) cheaper and (B) uses fewer of those 5VDC signals?
I know that if you have 5 bits of information, you can have 2^5 = 32 conditions. But is it possible to operate devics with just 5 on/off relays?
I can easilly picture a grid, with five switches forming rows and five switches forming columns. Then have an AND gate at each intersection. If the row AND column are turned on, then that lightbulb turns on. That gives just 10 relays needed. Is there a better way though? Also, are there AND gates available that operate at 24V and 1A?
Or is there any rotary switch that can handle 24V at 1A and is controlled by a 5VDC signal? I could use this to move from device to device. Then use one relay to turn on/off the power so that only the desired device is operating as the rotary switch moves to the next device.
