I want to turn 6 servos 90 degrees at the same time when a relay turns power on and all 6, 90 degrees back when it is turned off. What is the easiest option. The servos will be in the range of 150 inch ounces and all items involved will be near each other.
Connect all six servos to one pin. When you want then to turn use servo.write(90);. When you want them to turn back, use servo.write(0);.
There are many ways to determine when "a relay turns power on". What is controlling the relay? What are the specifications of the relay coil and contacts? What power is it switching? Are any of the contacts available for use?
The relay I am talking about already switches from an arduino I built that has pushbuttons to give different commands and different amounts of time according to which button is pushed. I know how to make the Arduino turn servos but want something else to do it when the relay the arduino operates turns on and off. Is there another way to turn servos or should I just get another arduino and have the relay switch it.
The easiest way would be to have the SAME Arduino that controls the relays also control the servos.
If you don't want to use an Arduino to turn a servo you can provide the required pulse train with something else like a 555 timer chip circuit.
Thanks, I will look into that. I don't want to use the original arduino other than to trigger the servos because the box that the arduino is in needs to be by itself.
Connect all six servos to one pin.
Any downside to that, John?
(I won't even try to measure the current on a signal wire, since I'm sure my meter won't react quickly enough. I daresay it's uA or a couple of mA tops per servo so I doubt current's an issue.)