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	Subject - control question karlwayne For any control experts, is it possible to take an existing circuit - which has the switch leg of a photo eye feeding the coil of an ice cube relay, which in turn controls a latch/unlatch contactor [via of a three point contact (common - NC - NO)], and add to this circuit a two position selector switch to obtain manual overide? kbsparky You should be able to override the input of that relay if you have the source for that photocell available, as well as it's output. Merely wire your override switch in parallel with the source and the relay coil. You won't be able to manually override the lighting contactor to the "off" position with this setup once it gets dark out, however. rabbitgun I can help you out but I will need some info. 1. Are you using the ice cube to control an elect/mechanical contactor?( Do you need to power it to close it and then power it to open it.) 2. Do you want the selector switch to turn it off as well as on? 3. Or, explain again what you are trying to do. karlwayne Question #1 - yes Question #2 - yes Question #3 - Truthfully, I only gave half the story so as to not scare anybody away. There are two lighting contactors, both of which operate via of one photo-eye. One of the contactors is a 'normal' 120 volt coil. The second contactor is a latch/unlatch setup. I spoke with the customer and they want to be able to turn either contactor on and off manually. I told them I thought I could do that with two H/O/A switches, each having a contact block with 2 NO contacts, so I bought them before I drew up the new circuitry. The existing setup used two time clocks, of which they want to demo, and there is a 6 by 6 with two ice cubes in it. nfsus you could do this by using a rotary switch. pull power from the photo cell to yhe common on the switch, continue power leg to photocell from sw position 1. take a sw leg to the contact direct from the sw position 2. leave the 3rd contact open for the off position. rabbitgun http://www.villagephotos.com/pubbrowse.asp?folder_id=1253103 Here is a link to a quick sketch I did. I tried to show how you can use a simple single pole switch to control an ice cube that has Common,NO,NC to control your latching relay. If the ice cube is in an unpowered position you will take the power source for the latching relay through the C and NC contacts on the ice cube to the "open" contact on the latching relay. Power the ice cube and you will take power through the C and NO contacts to power the close contact. I showed two switches to control the two ice cubes but you could use one. I made an assumption that your two ice cubes are each controlling the two separate lighting contactors. I also do not know how the various power sources are used to feed the various relays so tried to leave that out of the sketch. I noticed I did not ID the photo cell but it is the square with a circle in it on the left side of the sketch. (But you knew that.) The over ride will only work to turn the lights off at night when the photo cell is powering the system. They will need to remember to turn the switches back on the next day in order to allow the photo cell to turn the lights back on the next evening. Hope that helps, or, gives you some ideas. Kent karlwayne Ken - nfsus - Kent, I'd just like to say thank-you for your time and effort spent to help out. I did manage to get this task completed without any egg on my face, but it's a good thing to know someone was backing me up if I goofed. I haven't figured out how to make a sketch in here yet, and I know I owe you a responce. I took the hot common to the: 1. photo-eye 2. hand pos. of HOA #1 3. hand pos. of HOA #2 4. common contact of IC #1 switch leg of the P.E. went : 1. auto contact of HOA #1 2. auto contact of HOA #2 jumpered load side of HOA #1 and went to coil of ice cube jumpered load side of HOA #2 and went to coil of Contactor #2 NC of ice cube went to unlatch coil NO of ice cube went to latch coil didn't use 2nd ice cube