Lighting Contactor Issue

[mgookin]

We manufacture outdoor light controls. We use the industry standard ANSI C136.10 twist-lock interface. Our product is listed 120-277VAC 1800VA. We have installations throughout North America, Europe and Australia without a single failure, except this one contactor which eats up our product, and it's a different issue every time.

So we went outand did some research. Here are our findings:
The lights are 480VAC single phase.
The contactor is a Square D series 8903 type SQH63 plus twist lock receptacle and lightning arrestor (form G101Y1532).
Contactor rating = 100A.
Load = 53 *400W = 21.2kVA /480 = 44A.
The contactor coil is 240VAC single phase.
Measuring from neutral to line at the twist-lock receptacle, we read 240VAC.
Measuring from neutral to control at the twist-lock receptacle, we read 0 VAC when the relay is open, and 240VAC when the relay is closed.
The load on the contactor coil is only pulling 0.095A = 22.8VA
But when we measure from hot to control at the receptacle with the relay closed, we measure 480VAC.

The city engineer seems to think it’s normal to measure 480VAC across the line and load at the receptacle and Square D seems to think something’s wired wrong.

We have plenty of other 240/480 installations on the same series contactor with zero problems to date. Just this one.

Can anyone tell me what’s going on here?

 

[Smart $]

With the info provided, I doubt it. Definitely something is wired wrong... or something is faulting.

480V hot to control at receptacle when contactor is energized seems to indicate something wrong with your equipment... but that is assuming your equipment is what is energizing the contactor coil. Even so, 480V to these terminals indicates L2 is being used or faulting somewhere on the contactor side.

If contactor was not energized by your equipment, such as energized with a manual override switch on the contactor side of the receptacle, then it would simply indicate the contactor side is wired wrong and using L2, or faulting to L2.

To speculate further requires more details on how the entire system is powered and controlled.

 

[GoldDigger]

We manufacture outdoor light controls. We use the industry standard ANSI C136.10 twist-lock interface. Our product is listed 120-277VAC 1800VA. We have installations throughout North America, Europe and Australia without a single failure, except this one contactor which eats up our product, and it's a different issue every time.

So we went outand did some research. Here are our findings:
The lights are 480VAC single phase.
The contactor is a Square D series 8903 type SQH63 plus twist lock receptacle and lightning arrestor (form G101Y1532).
Contactor rating = 100A.
Load = 53 *400W = 21.2kVA /480 = 44A.
The contactor coil is 240VAC single phase.
Measuring from neutral to line at the twist-lock receptacle, we read 240VAC.
Measuring from neutral to control at the twist-lock receptacle, we read 0 VAC when the relay is open, and 240VAC when the relay is closed.
The load on the contactor coil is only pulling 0.095A = 22.8VA
But when we measure from hot to control at the receptacle with the relay closed, we measure 480VAC.

The city engineer seems to think it?s normal to measure 480VAC across the line and load at the receptacle and Square D seems to think something?s wired wrong.

We have plenty of other 240/480 installations on the same series contactor with zero problems to date. Just this one.

Can anyone tell me what?s going on here?

Well, I am just guessing, since your use of the word "control" does not fit with the simplest configuration. Are you calling the relay coil terminal "control" and expecting it to attach to the Load terminal of the receptacle?

The standard C136.10 has Neutral, Line and Load, and no auxiliary circuits.
In that situation your controller would use power from Line to Neutral (if necessary) to control normally single pole contacts which bridge line to load when dark.

Since the lighting is 480 and your controller is only rated up to 277, you have to control a contactor rather than the actual lighting load. Am I correct so far?

Or does your rating cover split phase 240/480 as long as there is never more than 240 to ground/neutral on any terminal?

Next assumption: You describe the feed as 480 single phase. Do you really mean 240/480 split phase? If not, where is the 240 for the contactor relay coil coming from?

First conclusion: If 480 is present between the line and load terminals at any time when your device is plugged in, something is wired wrong.
It would be fine to see 480 from line to load if they were using a 480 volt rated control, which yours is not!

Figuring out just what is wrong is another story. My first guess is that instead of properly using a two pole contactor to open both sides of the lighting load they are trying some weird circuit to use your device to open one side and the contactor to open the other. That is pretty much guaranteed to expose your control to at least transient 480 somewhere along the way.

I really do not understand what you mean when you say that there is 480 from line to load when the relay is closed. By relay do you mean the contactor?
It is closed when your device is open from line to load? Or is someone pushing the armature in to test?

But I guess the real question which should answer everything is: What voltages do you measure under exactly the same test conditions at a site which does not eat your controls???

 

[GoldDigger]

But I guess the real question which should answer everything is: What voltages do you measure under exactly the same test conditions at a site which does not eat your controls???

Looking at the catalog entry for the contactor/disconnect/box combo, I see that it can be ordered with auxiliary holding contacts for electrically held latching. Are those present in the unit in question? If so it might cause some strange voltages on the coil terminals if wired incorrectly.

 

[don_resqcapt19]

A circuit drawing would be very helpful, especially with the points where the voltage readings were taken labeled on the drawing.

 

[Smart $]

Looking at the catalog entry for the contactor/disconnect/box combo, I see that it can be ordered with auxiliary holding contacts for electrically held latching. Are those present in the unit in question? If so it might cause some strange voltages on the coil terminals if wired incorrectly.

Didn't look at specifics, but that's usually a means to control energizing/deenergizing the coil with a trigger pulse. Currently doubt that is type of control being used.

 

[GoldDigger]

Didn't look at specifics, but that's usually a means to control energizing/deenergizing the coil with a trigger pulse. Currently doubt that is type of control being used.

I do too, but if the installation is miswired in the first place, who knows.

 

[mgookin]

Well, I am just guessing, since your use of the word "control" does not fit with the simplest configuration. Are you calling the relay coil terminal "control" and expecting it to attach to the Load terminal of the receptacle?

The standard C136.10 has Neutral, Line and Load, and no auxiliary circuits.
In that situation your controller would use power from Line to Neutral (if necessary) to control normally single pole contacts which bridge line to load when dark.

Since the lighting is 480 and your controller is only rated up to 277, you have to control a contactor rather than the actual lighting load. Am I correct so far?

Or does your rating cover split phase 240/480 as long as there is never more than 240 to ground/neutral on any terminal?

Next assumption: You describe the feed as 480 single phase. Do you really mean 240/480 split phase? If not, where is the 240 for the contactor relay coil coming from?

First conclusion: If 480 is present between the line and load terminals at any time when your device is plugged in, something is wired wrong.
It would be fine to see 480 from line to load if they were using a 480 volt rated control, which yours is not!

Figuring out just what is wrong is another story. My first guess is that instead of properly using a two pole contactor to open both sides of the lighting load they are trying some weird circuit to use your device to open one side and the contactor to open the other. That is pretty much guaranteed to expose your control to at least transient 480 somewhere along the way.

I really do not understand what you mean when you say that there is 480 from line to load when the relay is closed. By relay do you mean the contactor?
It is closed when your device is open from line to load? Or is someone pushing the armature in to test?

But I guess the real question which should answer everything is: What voltages do you measure under exactly the same test conditions at a site which does not eat your controls???

Receptacle wiring:
Neutral = white
Line = black
Load = red. (aka control)
Where I said "Measuring from neutral to control at the twist-lock receptacle..." that means white & red.

Our device is powered off the Line & Neutral; agreed.
And our device connects Line to Load at darkness; agreed.

The lights are 2 wire 480V single phase. It's a Florida Power & Light thing. Most contactors in the area for 480V lighting have a 240V circuit in the cabinet for the light control receptacle. I would guess there's a step down xfrmr in the cabinet but I'm not positive on that one.

I take voltage readings at the receptacle connections only. I don't care about the load side of the contactor.
At the receptacle when the light control relay is open (daytime)
White to Black = 240V
White to Red = 0V
Black to Red = 0V
At the receptacle when the light control relay is closed (night time)
White to Black = 240V
White to Red = 240V
Black to Red = 480V

With a closed relay I'm effectively probing two points on the same conductor (same path) and I'm not even probing a neutral.
Why is my meter saying 480V?

 

[Smart $]

...At the receptacle when the light control relay is closed (night time)
White to Black = 240V
White to Red = 240V
Black to Red = 480V

With a closed relay I'm effectively probing two points on the same conductor (same path) and I'm not even probing a neutral.
Why is my meter saying 480V?

As I said in my initial post...

...
480V hot to control at receptacle when contactor is energized seems to indicate something wrong with your equipment... but that is assuming your equipment is what is energizing the contactor coil. Even so, 480V to these terminals indicates L2 is being used or faulting somewhere on the contactor side.
...

Is your contact switching Control to Neutral or Control to Line? (I believe typical is the latter.) If Control to Neutral, it could explain 480V Line to Control... i.e. there is split-phase 240/480V in the contactor enclosure (designed or inadvertent... such as a control transformer wired in reverse polarity). If Control to Line, I can't see how the contactor even gets energized. As you said you are essentially reading voltage on two points on the same side of the load.

Can you get a contactor control drawing from the city engineer?

 

[GoldDigger]

With a closed relay I'm effectively probing two points on the same conductor (same path) and I'm not even probing a neutral.
Why is my meter saying 480V?

My guess, and I am reasonably confident in it, is that there is NOT a 240 volt stepdown transformer in the installation and that they have done something kludgy to get the 120 volts for the relay coil. Something like putting a fixed resistance in series with the coil maybe?

Normally a controller that plugs into a socket like that, for an individual light, will close the contacts (Line to Load) at night. So that would be pulling in the relay if they just replaced the lamp load with the relay coil.
But you are indicating that you are measuring voltage between your contacts when the relay is closed. I do not understand that either.
Are you probing the empty socket and forcing the relay closed, or are you measuring with your control in place?

 

[mgookin]

The relay in the controller is normally closed (fail-on for safety). The controller opens the relay during the daytime.

I'm not probing an empty socket. I'm measuring voltages on the white, black and red wires where the wires from the receptacle are wired to the contactor. And we have the ability in the field to make the controller think it's day or night to put the relay in whatever state we want to measure voltages in.

As to why I would measure voltage across the line and the load, that's a great question. I was out there with the city engineer the first time we had a problem and he did it to show me there's 480V there and asked if our relay was solid state or electromechanical because he said it would fry a solid state relay. Our relay is electromechanical.

I'm not understanding how we can measure voltage at two points along the same path while not even touching a neutral, and measure 480VAC, or at least that's what the meters (done it with two different meters) are telling us.

If you energize a bare wire with a load on it and place your volt meter probes at two different points along the same conductor, you would measure 0 Volts, right? Because the potential (difference) is zero.

 

[Smart $]

The relay in the controller is normally closed (fail-on for safety). The controller opens the relay during the daytime.

I'm not probing an empty socket. I'm measuring voltages on the white, black and red wires where the wires from the receptacle are wired to the contactor. And we have the ability in the field to make the controller think it's day or night to put the relay in whatever state we want to measure voltages in.

As to why I would measure voltage across the line and the load, that's a great question. I was out there with the city engineer the first time we had a problem and he did it to show me there's 480V there and asked if our relay was solid state or electromechanical because he said it would fry a solid state relay. Our relay is electromechanical.

I'm not understanding how we can measure voltage at two points along the same path while not even touching a neutral, and measure 480VAC, or at least that's what the meters (done it with two different meters) are telling us.

If you energize a bare wire with a load on it and place your volt meter probes at two different points along the same conductor, you would measure 0 Volts, right? Because the potential (difference) is zero.

Taking into consideration your posted readings...

At the receptacle when the light control relay is open (daytime)
White to Black = 240V
White to Red = 0V
Black to Red = 0V
At the receptacle when the light control relay is closed (night time)
White to Black = 240V
White to Red = 240V
Black to Red = 480V

...it seems to me your readings are backwards, coupled with the contactor coil using the other leg of a split-phase supply. Here is what readings would be, assuming your controller switches Black to Red...

At the receptacle when the light control contact is open (daytime)
White to Black = 240V
White to Red = 240V
Black to Red = 480V
***Same as what you stated for closed/night time

At the receptacle when the light control contact is closed (night time)
White to Black = 240V
White to Red = 240V
Black to Red = 0V
***Top and bottom values same as what you stated for open/daytime, but middle is different

The only way you should read any voltage above insignificant across Black to Red is when your controller contacts are open. When your controller contacts are closed, you should read ~0V Black to Red.

Any way you go about it, your controller is rated 120-277VAC and there definitely appears to be 480VAC there.

As to why there is 480V there, perhaps the engineer or whoever wired it thought your controller switched Red to Neutral rather than Red to Black...???

 

[hurk27]

The relay in the controller is normally closed (fail-on for safety). The controller opens the relay during the daytime.

I'm not probing an empty socket. I'm measuring voltages on the white, black and red wires where the wires from the receptacle are wired to the contactor. And we have the ability in the field to make the controller think it's day or night to put the relay in whatever state we want to measure voltages in.

As to why I would measure voltage across the line and the load, that's a great question. I was out there with the city engineer the first time we had a problem and he did it to show me there's 480V there and asked if our relay was solid state or electromechanical because he said it would fry a solid state relay. Our relay is electromechanical.

I'm not understanding how we can measure voltage at two points along the same path while not even touching a neutral, and measure 480VAC, or at least that's what the meters (done it with two different meters) are telling us.

If you energize a bare wire with a load on it and place your volt meter probes at two different points along the same conductor, you would measure 0 Volts, right? Because the potential (difference) is zero.

First the only way for you to have 480 volts across your red and black is the other side of the contactor coil is connected to another hot on the 480 volt side, this would most likely take out the coil on the contactor as well as your controller so someone defiantly has some wires crossed, if the control circuit is only connected to the 240 volt supply including the coil you should only have 240 volts across the black and red.

Fail on lighting will have NC contacts on the contactor so that when power is removed from the contactor the lights come on, your controller should energize the coil during the day and remove power during the night, in post 8 you claim that your device powers the contactor at night and removes power during the day, this would not be correct for a fail safe Normally closed lighting contactor.

I have no idea of how the 240 volts is supplied to the control circuit, your device as well as the coil of the contactor should only be connected to the 240 volt side of this supply, you keep saying neutral conductor which in a single two wire output transformer you would not have a neutral but maybe a grounded conductor like when you ground one side of the control transformer, if the utility is supplying the lighting from a center tapped 480/240 volt single phase transformer then you will have a grounded/neutral conductor brought into the panel, this same grounded conductor must also land on one side of the contactor coil other wise you will have the 480 volts across the coil when your device closes, so look at the contactor coil make sure it is a 240 volt coil and the return side is in-fact connected to the grounded conductor not the other hot coming from a center tapped transformer which is the only way you would be getting 480 volts.

If your device is not capable of switching from nighttime energizing to daytime energizing then you will need to add a relay with a normally closed contact so when you controller shuts off in the daytime the contactor energizes and open the contacts controlling the lights, then when your controller turns on at night the relay pulls in and removes the power to the lighting contactor which the NC contacts closes and turns the lights on, we had to do this with a photo cell as sometimes a NC photo cell could not be obtained.

Some of these line voltage contactors will come with a jumper to one of the line side contacts to supply one side of the coil, if this is the case then this jumper must be removed if the line voltage for the lights is not the same voltage that the coil is rated at, then this side of the coil must be re-connected to the grounded conductor so it is supplied with 240 volts.

I would really try to get a wiring diagram that this control panel is supposed to be wired from, because it sounds like that as now the contactor coil is wired for the full 480 volts or maybe they are expecting your device to switch the grounded side which no photo cell or your controller is able to do so as it is a 3-wire device which shares the line hot as both supplying voltage to your GPS electronics as well as supplying the line side of the relay in your device which switches the red output connection, like I said above it should only take switching the non-controlled side of the contactor coil from being supplied from another hot, to being supplied from the grounded conductor.

 

[hurk27]

The relay in the controller is normally closed (fail-on for safety). The controller opens the relay during the daytime.

I'm not probing an empty socket. I'm measuring voltages on the white, black and red wires where the wires from the receptacle are wired to the contactor. And we have the ability in the field to make the controller think it's day or night to put the relay in whatever state we want to measure voltages in.

As to why I would measure voltage across the line and the load, that's a great question. I was out there with the city engineer the first time we had a problem and he did it to show me there's 480V there and asked if our relay was solid state or electromechanical because he said it would fry a solid state relay. Our relay is electromechanical.

I'm not understanding how we can measure voltage at two points along the same path while not even touching a neutral, and measure 480VAC, or at least that's what the meters (done it with two different meters) are telling us.

If you energize a bare wire with a load on it and place your volt meter probes at two different points along the same conductor, you would measure 0 Volts, right? Because the potential (difference) is zero.

Receptacle wiring:
Neutral = white
Line = black
Load = red. (aka control)
Where I said "Measuring from neutral to control at the twist-lock receptacle..." that means white & red.

Our device is powered off the Line & Neutral; agreed.
And our device connects Line to Load at darkness; agreed.

The lights are 2 wire 480V single phase. It's a Florida Power & Light thing. Most contactors in the area for 480V lighting have a 240V circuit in the cabinet for the light control receptacle. I would guess there's a step down xfrmr in the cabinet but I'm not positive on that one.

I take voltage readings at the receptacle connections only. I don't care about the load side of the contactor.
At the receptacle when the light control relay is open (daytime)
White to Black = 240V
White to Red = 0V
Black to Red = 0V
At the receptacle when the light control relay is closed (night time)
White to Black = 240V
White to Red = 240V
Black to Red = 480V

With a closed relay I'm effectively probing two points on the same conductor (same path) and I'm not even probing a neutral.
Why is my meter saying 480V?

If the lighting contactor is a fail safe (ON) normally closed contactor so if the control fails the lights would stay on, then you controller would also have to be a normally closed control meaning that the red and black would have to close during the day time to energize the lighting contactor to open the contacts to turn off the lights, at night your controller would open the red and black thus de-energizing the lighting contactor which would close it NC contacts and turn on the lights.

If the control circuit is supplied with 240 volts and has a 240 volt rated coil then this is what you should see at your conductors to your twistloc in a normally close system (fail ON):

Daytime
White to black 240 volts. (A leg of supply)
White to red 240 volts. (A leg of supply)
red to black 0 volts (A to A leg of supply)

Nighttime
White to black 240 volts (A leg of supply)
White to red 0 volts (referenced through coil to neutral)
Red to black 240 volts (A leg to neutral reference through coil of supply)

If the coil is (like I suspect) fed from the other side of the transformer(480 volt side)
Then here is what you should find at your twistloc conductors:

Daytime
White to black 240 volts (A leg of supply)
White to red 240 volts (A leg of supply)
red to black 0 volts (A leg to A leg of supply)

Nighttime
White to black 240 volts (A leg of supply)
White to red 240 volts (reference through coil to B leg of supply)
red to black 480 volts (A to B legs of supply)

leg of supply is just a single phase hot neutral hot on a center tapped transformer A/N/B where you would have A to N 240 volts B to N 240 volts and A to B 480 volts

If you had what most of us would call a normal non-fail ON system these are the voltages you would have

Daytime
White to black 240 volts (A leg of supply)
White to red 0 volts (reference through coil to neutral)
red to black 240 volts (A to N through coil of supply)

Nighttime
White to black 240 volts (A leg of supply)
White to red 240 volts (A leg of supply)
red to black 0 volts (A to A leg of supply)

And if the non-switch side of the coil is fed from the B leg of the supply (480 volts) then instead of the 240 volts on the red to black for day time above you would read 480 volts.

A normally close controller/photo cell should have a closed contact in the daytime and an open contact at night, and the fail safe normally closed lighting contactor will have a closed contact when not energized and a open contact when energized so the controller will have to energize the contactor in the daytime to turn off the lights.

 

[mgookin]

I'll do a cad drawing at the office tomorrow. Thanks very much for everyone's input.

 

[mgookin]

Controller:
1 form B (normally closed)
Electrically held (non-latching)

Contactor:
Normally open (must apply power to coil to turn lights on)
Electrically held


Testing with volt meter

Daytime:
Testpoints 1&2 = 240 VAC
Testpoints 1&3 = O VAC
All that?s normally expected.

Night:
Testpoints 1&2 = 240VAC
Testpoints 1&3 = 240VAC
And all that?s normal, so far.
But then the city engineer puts volt meter probes on Testpoints 2&3 and it reads 480VAC and that's confusing me. How do we measure 480 volts when we're effectively measuring two points along the same path? I'm saying same path because the relay is closed at this point. And the only thing going in to it is 240 volts.

Thanks.

 

[Smart $]

....
But then the city engineer puts volt meter probes on Testpoints 2&3 and it reads 480VAC and that's confusing me. How do we measure 480 volts when we're effectively measuring two points along the same path? I'm saying same path because the relay is closed at this point. And the only thing going in to it is 240 volts.

You said at the beginning...

except this one contactor which eats up our product

Was the contactor energized (i.e. contacts closed, lights on) at the time the 480V was measured?

Obviously there is 480V applied to the contactor subcircuit (contactor coil and controller contact in series). If the controller contacts are only rated 277V max, there may have been and likely was 480V across the controller's contacts, which likely resulted in excessive arcing across contacts on closing and opening. Subsequent pitting and other degradation result including contact resistance. At the time the voltage was measured, the resistance was high enough to cause a substantial voltage divider of contactor coil and controller contacts... to the degree of measuring a full 480V across the contacts is suspect, but does it really matter where you measured 480V?

 

[GoldDigger]

View attachment 8530
Controller:
1 form B (normally closed)
Electrically held (non-latching)

Contactor:
Normally open (must apply power to coil to turn lights on)
Electrically held


Testing with volt meter

Daytime:
Testpoints 1&2 = 240 VAC
Testpoints 1&3 = O VAC
All that’s normally expected.

Night:
Testpoints 1&2 = 240VAC
Testpoints 1&3 = 240VAC
And all that’s normal, so far.
But then the city engineer puts volt meter probes on Testpoints 2&3 and it reads 480VAC and that's confusing me. How do we measure 480 volts when we're effectively measuring two points along the same path? I'm saying same path because the relay is closed at this point. And the only thing going in to it is 240 volts.

Thanks.

I see several murky areas in the diagram.
1. Is the other end of the contactor coil, the one you are NOT connected to, grounded or connected to what you call the 240 volt neutral?
2. Is there a chance that the engineer's test point 3 is actually on the other terminal of his contactor coil?

I still would like some confirmation of where the 240 volts and the "240 volt neutral" are coming from. Since the supply is straight 480 with no neutral, there would have to be a transformer. And if neither side of the 480 is grounded, there would not necessarily be a grounded conductor (or neutral for that matter) for the 240 volt secondary.
If the line at your test point 1 is actually one side of the 480 and the line at your test point 3 is actually halfway between the two 480 lines, or the line at your test point 3 is actually the hot side of the 480 and test point 2 is at 240 volts above "ground" and the engineer is measuring the wrong end of the coil as his test point 3, that might(?) explain the whole voltage list. Is there any way to access via a test point the other (third) wire on your controller instead of at the contactor?

 

[mgookin]

City engineer came by today and clarified some misunderstandings.

First and most importantly, that's a 480V coil on the contactor. He should have never installed the 120-277V controller on that contactor. He had previously told me that was a 240V coil. The rating is right on the label on the product in plain english.

The controller which he brought back tested fine at 120, 240, 277 & 305V 60Hz tests in our lab today and there are no signs of excessive arcing on the relay contacts. I'm not understanding why his crew removed our controller. I saw that controller work fine for 10 days before they took it out.

There had been a previous issue with a resistor being under-rated and another issue where one of our engineers caused excessive force on a cold connection which were causes of two previous failures on that same contactor. That's why in the original post I said this contactor was eating our product up. The contactor is just doing its job.

His 480 for the highway lighting is two hots; no neutral on the 480. There is a seperate neutral brought into the cabinet to provide for 240V in-cabinet lighting using one hot and the neutral, and also to bond the cabinet to make it safe.

To answer some of the questions:
We were measuring voltages where the receptacle leads connect inside the cabinet; we were not probing an empty receptacle.
The 480V reading on the Line & Load receptacle leads occurs when the relay is closed (night time with lights on).
In the daytime it reads 240V neutral to line and 0V neutral to load.

Regarding measuring the 480V Line to Load at night, shouldn't I have to be measuring voltage on the load side at night with one probe and on the other side of the 480V coil with the other probe to measure 480V? I still don't understand why I'm reading 480V Line to Load on the receptacle connections at night when it's 240V Neutral to Line. Funky wiring or is it me? (boy I set myself up for that one )

Thanks again for all the replies.

 

[Smart $]

To answer some of the questions:
We were measuring voltages where the receptacle leads connect inside the cabinet; we were not probing an empty receptacle.
The 480V reading on the Line & Load receptacle leads occurs when the relay is closed (night time with lights on).
In the daytime it reads 240V neutral to line and 0V neutral to load.

With the engineer's information update the measurements should be...

Line to Neutral: 240V at all times

Night:
Line to Load ~0V
Neutral to Load ~240V

Day:
Line to Load ~480V
Neutral to Load ~240V

Regarding measuring the 480V Line to Load at night, shouldn't I have to be measuring voltage on the load side at night with one probe and on the other side of the 480V coil with the other probe to measure 480V? I still don't understand why I'm reading 480V Line to Load on the receptacle connections at night when it's 240V Neutral to Line. Funky wiring or is it me? (boy I set myself up for that one )

You are correct. At night, you should have measured ~480V from receptacle Load terminal (wired to one side of contactor coil) to other side of contactor coil, and ~0V from receptacle's Line to Load.