Pedestal Tester
Several weeks ago we posted a link to a pedestal tester that shows several pics. of a home made tester. http://www.myrv.us/electric/Pg/tester_50amp.htm Several members have ask about a written "How To" build one of these and if we had a wiring diagram. We have been it contact with these members by P/M and have come up with "some how to notes" , a rough wiring diagram, and a shopping list. Now this is not by any means the "bible" on how this can be done nor made to NEC codes but it is the basic stuff you will need to accomplish a product that will function at a reasonable cost. If you feel that you need to produce a tester that is to NEC standards go for it as that info is out there. Also this is the first draft and we may need to add to this after the roll out so this will be a work in progress.
Most of the needed parts can be got at a home improvement store and harbor freight type store except for the indicator light and the AC volt meters.
The "Shopping list"
1- Camco 55255- 50 amp plug or if you want to save a $ 1-Utilitech 50amp plug #4506 (which may take some modifying)
18"- #12 or #10 4 conductor THHN
1- Gampak 3/4" connector #49660
1- double gang metal box Racor # 683 or 8192
1- double gang plug cover Racor # 907C
2- 15 amp plugs Eaton # 5270-w
2- Harbor Freight Receptacle tester # 32906
2- AC voltage line meters #12-4055 If you want to get fancy they make these in digital
1-220V indicator/pilot light with leads #NL276WL3A-VDE or #134581
"The Notes"
These are not in any order of importance just info that you need to accomplish this DIY project.
1. If you buy the 50amp male plug from the home improvement store (like the one listed) you may have to take a die grinder, file, or sand paper to the top of the "U" shaped ground leg and make the top portion more rounded. Doing this will make it so the male plug will go into the female plug easier.
If you use the Camco it will save you from having to worry about the fit of the ground post. (this route will cost you a few $ more)
1a. The ground is the round or "U" shaped blade. (depending on your plug selection) Wire color is Green.
1b. The neutral is the lower center blade. Wire color is White.
1c. Line #1 is Red (one of the outside straight blades)
1d. Line #2 is Black (the other outside straight blade)
2. Red wire goes to the positive side of 1 of the 15 amp plugs this is line #1
3. Black wire goes to the positive side of 1 of the 15 amp plugs this is line #2
4. The white wire will have to be tied to both 15 amp plugs on the neutral side.
5. The green wire will have to be tied to both 15 amp plugs on the ground screw.
6. The positive side of the 15 amp plugs are the small blade.
6a. On the back of the 15 amp plug the positive side will be brass colored screws.
7. The neutral side of the 15 amp plugs are the large blade.
7a. On the back of the 15 amp plug the neutral side will be silver colored screws.
8. The ground side of the 15 amp plug is the round hole.
8a. On the back of the 15 amp plug the ground will be the green colored screw (1).
9. The 220v indicator light has to be tied to the positive side of both plug #1 and plug #2.
9a. Hook one wire from indicator light to one of the brass colored screws on one of the 15 amp plugs.
9b. Hook the other wire from the indicator light to one of the brass colored screws on the other 15 amp plug.
10. The indicator light can be mounted in one of the knock outs. Ours is mounted in the knock out next to where the cable comes into the box.
11. # 12 wire will work better for your 15 amp plugs if you can find it in a 4 wire cable. I used #10- 4conductor because it is what I had at home. If #10 is all you can find you may have to make some jumper wires that come off the 15 amp plugs and tie these wires to your main cable with wire nuts.
12. When you are plugged into a properly wired 50 amp pedestal receptacle you should have the indicator light shining. If you take a meter and measure between the 2 hot 15 amp plugs (small blades) you should have ~230 volts.
12a. If you are hooked up to a "false 50 amp" the indicator light will not be on. If you measure the same 2 blades you will have 0 volts, but if you measure between a hot blade and neutral (large blades) you should have ~120 volts.
12b. Even with a false 50 the 2 receptacle testers will be lit.
12c. Even with a false 50 the 2 volt meters will show voltage.
13. Due to space we have to plug our meters in crisscrossed, that is one side is up side down to the other.
"The wiring diagrams"
We can't draw on the computer so Mike sketched out some wiring schematics and took some pictures of them. Best as we can do as of right now.
Topic: Pedestal Tester