Ranco wiring

I recently bought a Ranco temperature controller off of ebay and need some help wiring the thing up. I'm clueless reading the schematics that came with the thing.

If someone could PM me and walk me through it, I'll take detailed photos of the process and wiki the thing for future electronic noobs!

Search this site for Ranco wiring. This question is answered several times.

Yuri_Rage said:

Search this site for Ranco wiring. This question is answered several times.

Click to expand...

Thanks. I did do that, but all I found was a variation of, "Search this site for Ranco wiring. This question is answered several times"...... or... "if you don't know how to do it, find someone that does and trade them some homebrew."

I was hoping that someone would PM me and walk me through it and I would take detailed photos and post them so that other complete idiots like myself would have a useful guide.

Ranco ETC-111000-000?



120 VAC is the line coming from the wall
120 Volt load is the line going to the device you are controling

If you can't follow the schematic, I don't suggest that you attempt to do the wiring yourself. Dealing with AC house current can be quite dangerous if you don't know what you're doing.

I hate to give you another answer you don't want to hear, but please find an electrician or at least a more DIY-savvy guy/girl to help you in person.

I apologize. I don't mean to come off as a smart ass in any way, and that's probably how the previous reply I gave sounds. The explanation of what comes from the wall and what goes out helps considerably. That's not explained in the instructions that came with the controller. The connecting lines don't make any sense though.

The schematic you posted is what I have from Ranco. I appreciate that wiring can be dangerous stuff, but I can't believe that it's so difficult that this can't be step by step explained. It can't be any more complex than say, installing a ceiling fan or ceiling light, which is a straight forward simple process that was easily diagrammed in a one page instruction sheet that even I could understand. Is this device considerably more complex? Maybe it is, because I look at the Ranco diagram and think whatthe... I just assumed that the instruction sheet that came with the Ranco was just very very poorly written.

Beerrific said:

Ranco ETC-111000-000?

View attachment 3493

120 VAC is the line coming from the wall
120 Volt load is the line going to the device you are controling

Click to expand...

Ok, I had some question when I wired mine up also. I got through it without burning the house down and it still is working like a champ. It is not as bad as you might think.

I start out buy cutting a 3 inch section from a extension cord. I use the three inch piece to get a couple of jumpers. You should use a three inch black and a 3 inch white jumper to do this job properly. O----------------- |------- |----------------E extract the center piece and you will wire the switch with the other two sides. That center piece is not junk it is your jumpers.Peal the ends and away you go.

1st. Your ground - wire it together.(The Ranco is not grounded) If you don't have a ground (green or just straight copper) just bypass this step. I used an orange extension cord 3 prong so it does use ground. I think it is best to as it can support the load of a freezer

2nd your hot lead. The white wire. You will need a 3 inch jumper (white) to do this piece. Connect the white lead (wire from the right side- the a/c "IN")and the jumper to the 120 connection and the other end of the jumper to the "C" screw. Then attach the "Out" hot lead (white wire from the left side - the a/c "OUT") to the BO screw. This is the switch connection. Hot lead here is the one set up for the switch to open and close. aka on/ off

3rd your common connection (Black wire).You will need a 3 inch jumper (Black) to do this piece. Connect your "Out" wire(Left) and "In" wire (Right) together with a small 3 inch jumper. So, Tie all three together with a wire nut. Then screw the other end of the jumper wire into the "COM" screw.

solder and tape all the connections as you deem necessary. Screw it down and plug it in.

the black wire is normally the "hot" wire which should go to the 120v screw which would be black or copper colored.

the white wire is normally the common or grounded wire which is normally a silver or green screw

switches should always be opened and closed from the hot side, not the cold side

This is why it's a bad idea to get wiring advice over the internet...two conflicting posts side-by-side (bentk and johnsmith above).

WHITE: COMMON

BLACK: HOT

GREEN: GROUND

Generally, DON'T connect the white wire to a green screw. Although common is ground referenced, that tends to be a good way to get shocked.

I am electrician and im up with the days but connecting small equipment reallys isnt that hard. This diagram is pretty much standard for anywhere in the US!

Yuri_Rage said:

This is why it's a bad idea to get wiring advice over the internet...two conflicting posts side-by-side (bentk and johnsmith above).

WHITE: COMMON

BLACK: HOT

GREEN: GROUND

Generally, DON'T connect the white wire to a green screw. Although common is ground referenced, that tends to be a good way to get shocked.

Click to expand...

Alright, I never mentioned the color of the screws, rather,I was referencing the color of the wires shielding. The screws in MY ranco are all silver. As I said in the post there is no place for a ground so by wiring the ground connection (the green shielded wire) together then you are still grounding the freezer you just can't ground the controller switch. In theory it should not matter to much if you wire through the white or the black wire. As I understand it, we use alternating current in the house so either way you are breaking the connection effectively.

The jumper information explains the schematics now. I think I undersatnd what to do. Thanks for the info!

I'll try to wire the thing up this weekend and take plenty of photos. Next week I'll either post a pictorial on the process or my wife will log on and tell you all where you can send memorial donations.

bentk said:

As I understand it, we use alternating current in the house so either way you are breaking the connection effectively.

Click to expand...

As johnsmith mentions, you should always make and break switched connections with the hot side. The reason is that hot carries current to the load. If you use common as the switched side, then any mistake on your part or any fault in the equipment may cause an unexpected result (i.e., the current may find its way to ground via another path).

johnsmith098 said:

If your not grounded you will never get shocked!

Click to expand...

This is very poor advice to give to people when you don't even know there skill level because depending on the system you are working this is not always the case.
A true statement is that you will never get shocked if you are at the same potential as the voltage you are working on.

I am curious as to were you served your apprenticeship...I served mine in Wisconsin and here it is a code violation to tie the grounded conductor to ground other then in a main panel or a separately derived system such as a transformer although I believe this is the case nation wide...
So the white wire is NEVER terminated on the grounding screw other then stated above this can lead to an electrocution hazard.

We should also clear up the nomenclature

Black wire = "hot" or Ungrounded conductor
White wire = "neutral* or common*" or Grounded conductor
Green wire = Grounding conductor

* Note: there is a difference between the term common and neutral but in this case it doesn't matter...

Very true guys. White is common Black is hot. I looked at my ranco and I am using black as the hot. Here I have corrected my instructions to reflect that. I believe that you would not hurt things too much if you had it swaped but never-the-less... Now, please if anyone has any problems with this let it be known.

I start out buy cutting a 3 inch section from a extension cord. I use the three inch piece to get a couple of jumpers. You should use a three inch black and a 3 inch white jumper to do this job properly. O----------------- |------- |----------------E extract the center piece and you will wire the switch with the other two sides. That center piece is not junk it is your jumpers.Peal the ends and away you go.

White = Common
Black = Hot
Green = Ground

1st. Your ground - wire it together.(The Ranco is not grounded) If you don't have a ground (green or just straight copper) just bypass this step. I used an orange extension cord 3 prong so it does use ground. I think it is best to as it can support the load of a freezer

2nd your hot lead. The black wire. You will need a 3 inch jumper (Black) to do this piece. Connect the black lead (wire from the right side- the a/c "IN")and the jumper to the 120 connection and the other end of the jumper to the "C" screw. Then attach the "Out" hot lead (Black wire from the left side - the a/c "OUT") to the BO screw. This is the switch connection. Hot lead here is the one set up for the switch to open and close. aka on/ off

3rd your common connection (white wire).You will need a 3 inch jumper (white wire) to do this piece. Connect your "Out" wire(Left) and "In" wire (Right) together with a small 3 inch jumper. So, Tie all three together with a wire nut. Then screw the other end of the jumper wire into the "COM" screw.

solder/ tape/wire nut all the connections as you deem necessary. Screw it down and plug it in.

wihophead said:

This is very poor advice to give to people when you don't even know there skill level because depending on the system you are working this is not always the case.
A true statement is that you will never get shocked if you are at the same potential as the voltage you are working on.

I am curious as to were you served your apprenticeship...I served mine in Wisconsin and here it is a code violation to tie the grounded conductor to ground other then in a main panel or a separately derived system such as a transformer although I believe this is the case nation wide...
So the white wire is NEVER terminated on the grounding screw other then stated above this can lead to an electrocution hazard.

We should also clear up the nomenclature

Black wire = "hot" or Ungrounded conductor
White wire = "neutral* or common*" or Grounded conductor
Green wire = Grounding conductor

* Note: there is a difference between the term common and neutral but in this case it doesn't matter...

Click to expand...

If your not grounded you are not completing the circuit theirfor it does not shock you. This is why we us insulated tools and rubber soled shoes. I took 2 years of trade school and have been licensed for 20 yrs. I dont belive I ever said you could put the neutral on the ground screw!

johnsmith098 said:

If your not grounded you are not completing the circuit theirfor it does not shock you. This is why we us insulated tools and rubber soled shoes. I took 2 years of trade school and have been licensed for 20 yrs. I dont belive I ever said you could put the neutral on the ground screw!

Click to expand...

Like I said it depends on the system you are working on...what about the case of 240V, 208V, 480V etc...(most people would see anything other then 240V but oh well) were you may be working with more then one ungrounded conductor. Someone could be working on a 240v heater or such and with your information they think they are safe if they are standing on a rubber mat or type of insulation and how do they know if they are even adequately insulated from ground. That is just bad information to give someone that is not trained....by the way I served a 10,000 hr state indentured apprenticeship and attended 3 1/2 years of class room training and I am a licensed Journeyman.
I work on equipment that is in the excess of 200KV were a rubber sole wouldn't help in the least not to mention once they are used and dirty any insulating factor has now been compromised....

I believe this is what you stated "the white wire is normally the common or grounded wire which is normally a silver or green screw" and if I took it the wrong way I apologize. Sorry to rant but in our union we preach safety...and I haven't even touch on the hazards of arc flash...lol

johnsmith098 said:

If your not grounded you are not completing the circuit theirfor it does not shock you. This is why we us insulated tools and rubber soled shoes. I took 2 years of trade school and have been licensed for 20 yrs. I dont belive I ever said you could put the neutral on the ground screw!

Click to expand...

John, how many regular joes have insulated tools lying around?????? I am an electrician too, but you don't tell inexperienced people something like that. I know that this is a very simple installation, but if someone posts that they don't understand the diagram, then they're unlikely to understand anything else that they are told about it over the internet. The best advice he can get is to have someone do it that knows what they are doing before he kills himself or burns the house down.
I have read a lot of posts in this forum from Handy Hank Homeowner giving electrical advice, and all I can do is roll my eyes and hope no one gets hurt. I know how to do it, you know how to do it, guys like Yuri and a few others know how to do it, but a lot of them don't, and chances are they aren't going to learn it on this forum, and trying to teach them isn't going to help. Why do you think that electrical apprentices aren't even allowed to work with hot circuits until their second or third year, and THEN only with supervision from a Journeyman or Master?

Rant over.

Alright then, you all got me convinced. I'm going to call a buddy from my old Guard unit who's a union electrician to do this so my children don't become fatherless when I snip the red wire instead of the green and the bomb goes off, or some such thing.


So there you have it... a noob who did search the forum before posting a question and who took advice....although, I can't help but suspect that, when demonstrated, wiring this thing is going to be as straightforward and simple as wiring a ceiling fan.

Cowgo: good call on calling in a buddy to help. I wired up my Ranco to my freezer my self and it was fairly strait forward once I deciphered the electrical lingo, but my first attempt to wire an ETC to a water heating element resulted in a fried ETC, $60 down the drain. I bet you can do it your self, but if you have a buddy who can walk you through it the first time you should be okay the next time you want to hook one up.

I teach new ppl on a regular basis every few years( most ppl dont have a clue).

I dont see the need to show my credits, but if you take my advice then take it as just that! with a grain or 2 of SALT