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How to add an Isolation Transformer to AV system.Thanks Bob!
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Nashou66



Joined: 12 Jan 2007
Posts: 16170
Location: West Seneca NY


PostLink    Posted: Fri Jul 11, 2008 12:21 am    Post subject: How to add an Isolation Transformer to AV system.Thanks Bob! Reply with quote


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I have had this ground lop problem and also a bit of a squiggle on vertical lines in my theater and tonight i finally found its source . I have a separate panel box that runs off my main Homes box. this box also has an installed surge protector. Its ground obviously is connected to the other panel box. This is where the problem arises, the main panel box's ground is connected to the copper piping on either side of my water meter, both these connections were heavily coroded. So I cleaned them up and the squiggly and hum is all but gone.

Is it possible to make a seaparate ground to a new grounding rod out side and not have it on the same ground as the other main panel box?

Will this cause any danger to the equipment on the smaller panel box.

And will this cause a difference in ground potential since the power is comming from the main Panel but the secondary panel box will have a separate ground?

What is the best way to combat this as i think my appliances and Air conditioner are the culprits here.

Athanasios

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Last edited by Nashou66 on Sat Aug 09, 2008 4:08 am; edited 4 times in total
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Tom.W



Joined: 09 Mar 2006
Posts: 6637



PostLink    Posted: Fri Jul 11, 2008 1:29 am    Post subject: Reply with quote

This might help...

http://www.harger.com/library/gb.cfm
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Boilermaker



Joined: 21 May 2006
Posts: 527



PostLink    Posted: Fri Jul 11, 2008 1:35 am    Post subject: Reply with quote

Yes and No. You should have only one ground for your entire electrical distribution system. If you decide to install your own ground rod, then you must disconnect the one to the water main.

Having said that - Your electric utility company must approve such a change. My guess is that they will require ground bonding at your water line, but they are the authority having jurisdiction in this case.

BTW, your main water line makes an excellent ground! You did the right thing by cleaning up the connection.

Bob
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Nashou66



Joined: 12 Jan 2007
Posts: 16170
Location: West Seneca NY


PostLink    Posted: Fri Jul 11, 2008 2:02 am    Post subject: Reply with quote

Thanks guys, I have to do a beter job of finding this annoyance, problem came back again. need to really clean the copper and then apply a protectant then connect it all up tot he proper torque. Also my Bly ray player is causing most of the issues from the HDMI cable I put a ground wire from the players chasis to the ground connector on my Monster power sourc but still get a slight hum in my speakers and slight horizontal oscilating movement in my video causing the vertical lines to look squiggly. pain in the arse !!!

Athanasios

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dbaisey



Joined: 09 Mar 2006
Posts: 821
Location: Southern Cal LA / Seattle WA


PostLink    Posted: Fri Jul 11, 2008 3:52 am    Post subject: Reply with quote

If you have cable try removing to see if the hum goes away. This is connected to chassis ground so gets into the whole system. If it goes away go look at the shield ground connector block that should be earth grounded. Might check your phasing also.

I had one that had noise and it was from a temp controlled aquarium pump. Triac dimmers etc
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Boilermaker



Joined: 21 May 2006
Posts: 527



PostLink    Posted: Fri Jul 11, 2008 11:54 am    Post subject: Reply with quote

Athanasios,

I have a recommendation for your woes. It is inexpensive, but it will work.

Several years ago I made this recommendation on the Tweaks forum at the other site and it started a flame war by people saying you have to buy all kinds of expensive high end gizmo's, so I have never been back to that Tweaks and never will!

You can obtain an isolation transformer in sizes from 5KVA on up on e-bay for little to nothing. The vast majority of these are designed and used for the healthcare industry for use in invasive procedure areas to eliminate the possibility of micro shock death.

They are almost all configured for a 120 volt output with a 208 volt primary because that is what is used in healthcare, so you will have to also buy an innexpensive and small "buck-boost" transformer to install on the primary side.
Feed this with a two pole breaker from one of your panels, and have the secondary side feed a small as you can find breaker panel which can serve all your equipment circuits.

This is completely legal and also provides additional safety. If you spend more than a few hundred dollars you did something wrong!

To show how isolated this is, the NEC (National Electric Code) considers this a separately derived source. It is so isolated that you can hold your hand on the black (120 volt power lead going to your recepticles) and your other hand on the ground lead and not feel a thing!

I have a gazillion things plugged into my isolated system for bothaudio and video and have never-ever had the slightest hum problem from either audio or video.

Just a thought.

Bob
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Nashou66



Joined: 12 Jan 2007
Posts: 16170
Location: West Seneca NY


PostLink    Posted: Fri Jul 11, 2008 1:40 pm    Post subject: Reply with quote

This is the cheapest one I found it looks like a nice high end piece but more than you suggest I pay but not by far? it it easy to hook up myself or can I higher an electrician to do it for me? I have a separate panel box all ready installed in my equipment room. Would it be as easy as shutting off the main sub panel breaker off on the main and then disconecting the power lines into the sub panel box and routing them through the issolation transformer?

http://cgi.ebay.com/MGE-ULTRA-ISOLATION-TRANSFORMER-91005-31T-NICE_W0QQitemZ330250697312QQihZ014QQcategoryZ78201QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

I checked the web site for it and its the 5KVA unit.

http://www.pacificparts.com/vends/mge/images/t1.pdf



Athanasios

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Boilermaker



Joined: 21 May 2006
Posts: 527



PostLink    Posted: Fri Jul 11, 2008 1:53 pm    Post subject: Reply with quote

Athanasios - That one will work perfectly. It has multiple input taps so you would not need a buck-boost transformer. It is expensive because it is new. I really wouldn't worry about a used one as they have a typical lifespan of 50+ years.

Yes, you could hook it up yourself, and if you have any questions, I'll be glad to help you through it.

Since you already have a sub panel for your equipment, it would be real easy.
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Nashou66



Joined: 12 Jan 2007
Posts: 16170
Location: West Seneca NY


PostLink    Posted: Fri Jul 11, 2008 2:06 pm    Post subject: Reply with quote

Thanks Bob,

So looking at this pic here:

th loose wires are the ones that would be in line from the main panel I assume, what are the two other cut black wires for? Would one or both of these be what goes into the sub panel box replacing the original input from the main panel box?


Athanasios

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Don't blame your underwear for your crooked ass~ unknown Greek philosopher


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Boilermaker



Joined: 21 May 2006
Posts: 527



PostLink    Posted: Fri Jul 11, 2008 2:23 pm    Post subject: Reply with quote

Yes - I am sure that somewhere, probably on the cover or from their website there is a color code chart that will show which wires are used for which voltages. If you can get this to me, I can tell you exactly which wires go where.

Essentially, this will just interrupt your present feed to your sub panel. The only common wire between the input and the output will be the ground wire. The input and output common (usually white) are NOT tied together as you would normally think.

Bob
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Boilermaker



Joined: 21 May 2006
Posts: 527



PostLink    Posted: Fri Jul 11, 2008 3:16 pm    Post subject: Reply with quote

Athanasios,

One thing I need to mention. Since we don't have a schematic of the windings yet, I am going to assume that the secondary is 120 volts. If this is so, then when you connect it to your sub panel you will need to connect one wire to both legs of the input on your panel. Also, if there is a "bridge" between the neutral buss and the ground buss on this panel, it must be removed and you must make sure that all the feeds to your different circuits have their grounds and neutrals on the proper buss or you will totally negate the isolation that the transformer is supplying.

Bob
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Nashou66



Joined: 12 Jan 2007
Posts: 16170
Location: West Seneca NY


PostLink    Posted: Fri Aug 08, 2008 6:14 am    Post subject: Reply with quote

Well I got my Isolation transformer from e-bay, this thing is heavy!!!About 150 pounds for a small size maybe 16 inches long by 10 inches wide. Its 5KVA unit that should be enough for my panel box. I have to check the box out to see if its the right kind for this or I have to make it so the neutral and ground bus are not connected in any way.





Here is a great paper on Audio Visual power distribution and grounding:

http://www.middleatlantic.com/pdf/PowerWhitePaper4_07.pdf

I'll add pics of it soon: here is a link for now

https://www.flickr.com/photos/21885221@N04/albums/72157705257786994

Athanasios

_________________
Don't blame your underwear for your crooked ass~ unknown Greek philosopher


"Republicans believe every day is the Fourth of July, but the Democrats believe every day is April 15." --- President Reagan

One Smart Dog!!!

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Last edited by Nashou66 on Tue Jan 01, 2019 2:57 pm; edited 1 time in total
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Gary M.
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PostLink    Posted: Fri Aug 08, 2008 1:52 pm    Post subject: Reply with quote

Nashou66 wrote:
Well I got my Isolation transformer from e-bay, this thing is heavy!!!About 150 pounds for a small size maybe 16 inches long by 10 inches wide. Its 5KVA unit that should be enough for my panel box. I have to check the box out to see if its the right kind for this or I have to make it so the neutral and ground bus are not connected in any way.





Here is a great paper on Audio Visual power distribution and grounding:

http://www.middleatlantic.com/pdf/PowerWhitePaper4_07.pdf

I'll add pics of it soon: here is a link for now

http://gallery.me.com/nashou.66#100112

Athanasios


I wish I would have got that beast Athan Thumbs Up

that thing has dual primaries and secondaries in addition to a shield between them, wire it for balanced for even better performance than standard isolated and it will run a entire 20amp circuit still at 2.5kva

if you are wondering how

tie 4 and 5 together alone on the input side and run the hot input into 1 and the neutral input into 8, then on the output side you wire 9 into the hot on your outlets and 12 into the neutral on your outlets, tie 10 and 11 together along with the ground from the input side that you didn't connect to the transformer yet and the shields and connect to the ground on your outlets

that is a perfect unit for balanced power Shocked

-Gary
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Nashou66



Joined: 12 Jan 2007
Posts: 16170
Location: West Seneca NY


PostLink    Posted: Fri Aug 08, 2008 3:29 pm    Post subject: Reply with quote

Thanks for the Info gary but I think I will want the whole 5KVA. I have heard that some times balanced power is not always the right way to go.
I have all my power amps, my source gear, there will be two marquees, sattelite with outdoor antenna, a sling box and my home wireless router.
The questions I have are how and where to connect the power wires from my Main panel to the transformer, then to the Sub panel box. I'll add pics for anyones help.

I plan the have the Iso transformer right next tot he panel box and make the wires as short as possible, My equipment is just about 3-4 feet away.
This is how my sub panel box is connected now. 220 line form a 60 amp fuse from main panel box. Ground from sub goes to main panel.

What I want to do is put the Iso Trans right next to the sub panel box(have to find a way to mount it to wall) bring the 220 lines to the Iso Trans the the out puts to the sub panel which i have three outlets coming out of them where all me gear and power conditioners are connected to.

60 amp fuse in main panel box



Wires into sub panel box as is now from main panel box



Zoomed out view of sub panel



Bob told me to remove the surge protector in above picture, should I?

Primary input connection options



Inside panel of Iso Trans input connection block, braided wires are ground straps
one from Coil shield, one to box of transformer




Now this is my first question, the wires will be disconnected from my sub panel and connected to the
input side of the Iso Trans. But the connection shows only one spot for the Line(black wires) in and one neutral and
I have two lines going into the sub panel now. I assume each line is a 110 line. So where on the primary input side do i connect both?( Wireing Schematic at end o post)
Also where will the ground Wire from the Main panel box go to in the Iso Trans.

Now I'll ask about going from the Iso transformer to the sub panel box.

Output connection options



I want to use the 120 volt out option.

Internal connection block for output primaries



Now how do i connect the two bus bars of the hot lines in the panel box
from the outputs of the Iso Trans, I'll need two lines out wont I? or do I connect one and then tie the bus in the panel box together?
Or can i not tie 9 and 11 together with a jumper and run each to one bus bar of my panel box?
Also where do i tie in the ground wires from the Iso trans? Do i only ground the coil shield and not the ground
that goes to the Iso trans case since then it will be tied to the main panel box which I am trying to Isolate it from.?

here is the wiring schematic of the HP Isolation Transformer



I think I have a grasp on it , I think form the Iso outputs I only take one hot line to the sub panel box and then tie the bus bars together to get the 110 or 120(which should I configure for?) to the other bus bar.
Bob also told me to make sure the neutral bar and the ground bar in the sub panel bow have no connection between them or infinite impedance: his quote from an e-mail he sent me:

Bob wrote:
Second, concerning your sub panel: It is very important that the ground and
neutral busses are not tied together in any way. I would suggest turning off
the service breaker to your subpanel, disconnecting temporarily the neutral
feed at your subpanel, unplugging everything served by your subpanel, and
then checking for continuity between your ground buss and your neutral buss
at the subpanel. You should have infinite impedance (resistance).


This I still have to check.

Gary this is why I want to not go ballanced, bob said this:

Bob wrote:
Fourth, Since you have just a few circuits in your subpanel, it will be
IMPOSSIBLE to have a completely balanced load for your transformer. What
this means is that one of the two secondary windings will carry a greater
load than the other. This will cause a slight imbalance of the two voltages
and lower the overall load capacity of the transformer. That is why I am
going to recommend that you configure your transformer for a 120 volt
output. In this fashion, all voltage (and phase) will be identical at your
circuits. Also, since the loads are shared, you have the full 5KVA capacity.
All this requires is that you increase the size of the conductors feeding
your subpanel to double the current capacity as they will now have twice the
current. I don't know what size (or length) of feeders you are now using,
but from the picture, they are probably already big enough!!


I read up on it and I agree. Bob has been a big help with this so far
and I wanted to share this with everyone as I feel it will help many people
if they try it as well. At least I hope it will eliminate my grounding issues.

So in conclusion any other suggestion or ideas would be helpfull.

Athanasios

_________________
Don't blame your underwear for your crooked ass~ unknown Greek philosopher


"Republicans believe every day is the Fourth of July, but the Democrats believe every day is April 15." --- President Reagan

One Smart Dog!!!

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Last edited by Nashou66 on Tue Jan 01, 2019 3:03 pm; edited 1 time in total
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rabies_70



Joined: 15 Feb 2007
Posts: 1189
Location: Carlsbad, CA

TV/Projector: Sony G70Q


PostLink    Posted: Fri Aug 08, 2008 4:03 pm    Post subject: Reply with quote

Looking at the picture of your sub panel The green screw on your neutral bus bar may be a bonding screw ie bonding your neutral to the box and the grounds. Which would be wrong even if you weren't adding isolation. Thats a real easy fix if it's the case. Making sure the panel isn't energized, unscrew it. If it goes through the bar into the metal of the box, you were bonded. Leave it out. If it doesn't and its just a set screw. Square D used to include a green screw that looks just like that one with every panel they sold just for bonding the box. Thats the only reason I mention it.

That is a nice transformer by the way.

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Gary M.
Guest







PostLink    Posted: Fri Aug 08, 2008 11:14 pm    Post subject: Reply with quote

Athan, where you planning on running your subpanel off the output of this transformer? if so I am sorry for the misunderstanding, if you wanted to do balanced you would need to use the sub panel to feed the transformer one 20-amp circuit and then use the balanced output to feed the outlets

but if you are doing as you say that won't work as you have said

Balanced power is a whole other step up above isolated, you can connect any electronic device to it, you just can't connect lights, motors, etc., but all your HT gear pour it on it Thumbs Up

like I said that is a nice transformer there, how much did you pay for it Athan? did they have anymore? Mr. Green

-Gary
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Nashou66



Joined: 12 Jan 2007
Posts: 16170
Location: West Seneca NY


PostLink    Posted: Sat Aug 09, 2008 12:07 am    Post subject: Reply with quote

they had it for a buy it now for 489, I was bidding on another two that I thought i could get for less one was 5KVA the other 3KVA. So I figured I'd low ball and see what there counter offer was. I offered 250 and to my suprise they took it!!! Shipping was 120. This thing is as heavy as my Marquee!! I need to figure a way to strap it to my wall the sub panel box is. It looks like it was specially made and fed a single 240 line in,as thats how it was configured when i got it . I just do not know how to get my 60 amp fuse output from my main panel it comes out to the sub panel Via two 110 lines. as you can see one feeds the upper hot bus and the other the lower hot bus for a total of three circuit breakers being able to be fed on each bar. So the two questions are,

1) how do I connect two 110 lines to the primaries?
2) how do i connect a single 120 or 110 to the two hot bus bars in the sub panel?

Oh ! and that Sub panel box is for Equipment and router only. no Lights or motors beside the fans of the PJ's.

Gary there a few on e-bay right now. I was even thinking of going one step further for the marquees in the blend and get two smaller Iso's that can just be pluged in to the wall sockets so i'll have a cascading Isolation to my PJ? Would this be ok to do?


Athanasios

_________________
Don't blame your underwear for your crooked ass~ unknown Greek philosopher


"Republicans believe every day is the Fourth of July, but the Democrats believe every day is April 15." --- President Reagan

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Boilermaker



Joined: 21 May 2006
Posts: 527



PostLink    Posted: Sat Aug 09, 2008 12:10 am    Post subject: Reply with quote

Athanasios - Looks like its time to hook this big puppy up! Let me start from the feed and end at the load for logic. I f you have any questions at all, please let me know:

1 - At your main panel you said that you have 60 amp fuses. If this is correct, then the wires from this circuit must be of at least 60 amp capacity. I'm sorry that I don't remember what guage that is, but the older you get, the more memory you start to dump.

Actually, you only need slightly over 20 amps to maintain the full 5KVA rating. Unless you have a large distance to your xfmr., I would recommend using #10AWG with either a 20 or 30 amp fuse size. If you already have larger wire in place - no problem, just make sure the fuse is NOT larger than the wire capacity.

2 - You will need just two conductors plus ground from your main panel. A neutral conductor is not used. If your cable already has a neutral, just wirenut it off at both ends.

3 - These two wires will attach to terminals #1 and #8 at your transformer. It doesn't matter which one is which. I see that the "primary input" label on your transformer calls terminal #8 neutral. Ignore this for your application. Both wires are "Lines" and have 240 volts potential between them.

4 - The ground wire from your main panel will attach to the ground screw on the transformer box which should be bonded with the chassis. There will be others attached to this ground also, so it might be easier to pick up a little ground bar at an supply house or Lowes.

5 - Attach a jumper between terminals #4 and #5 at your xfmr. This will set it up for 240 volts input. We could have wired it for 120volt input, but this would present an unbalanced load to your main panel which is not good practice.

6 - Attach a jumper between terminals #9 and #11 and between terminals #10 and #12. Notice that while the primaries are wired in series, the secondaries are wired in parallel. This way there are twice as many primary windings as are in the secondary. This "ratio" is what determines the ratio of input voltage to output voltage - 240/120.

7 - Make sure there are no other jumpers are installed!

8 - Attach both of the braided copper shield wires to the ground bar on your xfmr. and also the ground wire on the cable feeding your sub-panel. There should be no other wires attached to this ground.

9 - Attach two conductors to terminals #9 and #10 respectively. While it really doesn't matter which one is which, I would use a white conductor on the #10 terminal and a black conductor on #9 just to look "proper". These conductors should be able to handle a little over 40 amps, so (still can't remember for sure) I would guess a #8AWG would get the job done. These are obviously feeds for your subpanel.

10- Assuming you have already determined the total isolation between your ground and neutral buss in your subpanel, attach the ground wire from the xfmr. to the ground buss bar in your subpanel.

11- Attach the white wire to the neutral buss bar in you subpanel.

12- Attach the black wire to one of the two line terminals at the top of your subpanel.

13 - Attach a jumper #8AWG black wire from the terminal used in #12 above to the other line terminal at the top of your subpanel.

You are done - Now here is how I would recommend you checking things out to avoid the "search and destroy" method!

1 - Unplug everything being served by your subpanel.
2 - Turn on the 240 volt supply to your xfmr.
3 - Measure the voltage between all three of your 20 amp circuit breakers output and the neutral buss - You should get 120 volts (or whatever your utility company sends you!
4 - Measure the voltage between any two circuit breaker outputs - You should get zero.
5 - Measure the voltage between any of the circuit breaker outputs to the ground buss - If you are using a modern VOM you will probably get some strange extraneous reading like 60 volts or something - If you are using an analog voltmeter (d-Arsonval movement) you will get zero. The reason you get a strange reading with a modern powered VOM is that they have an extremely high input impedance (usually in the 10's of millions of ohms) and while you have isolated power, there is still some leakage in the small microamp range which is insignificant. The analog meter has a much lower inut impedance and so will read zero as it should.
6 - Plug everything in and listen to the sound of silence!!!

Recommendations:

1 - Absolutely remove that device from your subpanel - move it to your main panel where it should be.
2 - If you are using any "power filters", also remove them as normal filter design will allow some leakage current which will somewhat defeat the purpose of isolated power. You will find you don't need them (actually if they worked, you wouldn't have bought this 150lb xfmr.). Sell them on fleabay and buy some new tubes for your blend.

Let me know how it works.


Bob
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perisoft



Joined: 29 Aug 2007
Posts: 2920
Location: Ithaca, NY


PostLink    Posted: Sat Aug 09, 2008 12:27 am    Post subject: Reply with quote

Welll... if you can get Optimus Prime and Bumblebee to take care of Starscream, you can probably separate Megatron.

Wait, am I missing something?

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Nashou66



Joined: 12 Jan 2007
Posts: 16170
Location: West Seneca NY


PostLink    Posted: Sat Aug 09, 2008 1:25 am    Post subject: Reply with quote

Boilermaker wrote:
Athanasios - Looks like its time to hook this big puppy up! Let me start from the feed and end at the load for logic. I f you have any questions at all, please let me know:

1 - At your main panel you said that you have 60 amp fuses. If this is correct, then the wires from this circuit must be of at least 60 amp capacity. I'm sorry that I don't remember what guage that is, but the older you get, the more memory you start to dump.

Actually, you only need slightly over 20 amps to maintain the full 5KVA rating. Unless you have a large distance to your xfmr., I would recommend using #10AWG with either a 20 or 30 amp fuse size. If you already have larger wire in place - no problem, just make sure the fuse is NOT larger than the wire capacity.

2 - You will need just two conductors plus ground from your main panel. A neutral conductor is not used. If your cable already has a neutral, just wirenut it off at both ends.

3 - These two wires will attach to terminals #1 and #8 at your transformer. It doesn't matter which one is which. I see that the "primary input" label on your transformer calls terminal #8 neutral. Ignore this for your application. Both wires are "Lines" and have 240 volts potential between them.

4 - The ground wire from your main panel will attach to the ground screw on the transformer box which should be bonded with the chassis. There will be others attached to this ground also, so it might be easier to pick up a little ground bar at an supply house or Lowes.

5 - Attach a jumper between terminals #4 and #5 at your xfmr. This will set it up for 240 volts input. We could have wired it for 120volt input, but this would present an unbalanced load to your main panel which is not good practice.

6 - Attach a jumper between terminals #9 and #11 and between terminals #10 and #12. Notice that while the primaries are wired in series, the secondaries are wired in parallel. This way there are twice as many primary windings as are in the secondary. This "ratio" is what determines the ratio of input voltage to output voltage - 240/120.

7 - Make sure there are no other jumpers are installed!

8 - Attach both of the braided copper shield wires to the ground bar on your xfmr. and also the ground wire on the cable feeding your sub-panel. There should be no other wires attached to this ground.

9 - Attach two conductors to terminals #9 and #10 respectively. While it really doesn't matter which one is which, I would use a white conductor on the #10 terminal and a black conductor on #9 just to look "proper". These conductors should be able to handle a little over 40 amps, so (still can't remember for sure) I would guess a #8AWG would get the job done. These are obviously feeds for your subpanel.

10- Assuming you have already determined the total isolation between your ground and neutral buss in your subpanel, attach the ground wire from the xfmr. to the ground buss bar in your subpanel.

11- Attach the white wire to the neutral buss bar in you subpanel.

12- Attach the black wire to one of the two line terminals at the top of your subpanel.

13 - Attach a jumper #8AWG black wire from the terminal used in #12 above to the other line terminal at the top of your subpanel.

You are done - Now here is how I would recommend you checking things out to avoid the "search and destroy" method!

1 - Unplug everything being served by your subpanel.
2 - Turn on the 240 volt supply to your xfmr.
3 - Measure the voltage between all three of your 20 amp circuit breakers output and the neutral buss - You should get 120 volts (or whatever your utility company sends you!
4 - Measure the voltage between any two circuit breaker outputs - You should get zero.
5 - Measure the voltage between any of the circuit breaker outputs to the ground buss - If you are using a modern VOM you will probably get some strange extraneous reading like 60 volts or something - If you are using an analog voltmeter (d-Arsonval movement) you will get zero. The reason you get a strange reading with a modern powered VOM is that they have an extremely high input impedance (usually in the 10's of millions of ohms) and while you have isolated power, there is still some leakage in the small microamp range which is insignificant. The analog meter has a much lower inut impedance and so will read zero as it should.
6 - Plug everything in and listen to the sound of silence!!!

Recommendations:

1 - Absolutely remove that device from your subpanel - move it to your main panel where it should be.
2 - If you are using any "power filters", also remove them as normal filter design will allow some leakage current which will somewhat defeat the purpose of isolated power. You will find you don't need them (actually if they worked, you wouldn't have bought this 150lb xfmr.). Sell them on fleabay and buy some new tubes for your blend.

Let me know how it works.


Bob



1) The wire is very thick about 1/4 inch maybe 6 guage?

2) Check, answered my main input power question.

3) Here you having it set up for 240 input I think my power company is 220 so should I connect to #7 and not #8 or will this not matter?

4) Each side of my xfmr has a ground screw,Primary and secondary sides, so should I add a buss to each side?

5) Gottcha unless i set it up for 220 input then I'd add a jumper to #3 and #5, right?

6 & 7) Gottcha !

8) Since i have two ground bonds, one on each side, I can attach one braid to the one side and one to the other side. No need to try to reach it to the other side of the xfmr. Right? And the sub panel to the secondary side ground the Main panel ground to the ground on the primary side, right?

9) Okee dokee.

10) Still need to measure continuity.

11 & 12) Gottcha

13) Tie together the two hot buss bars in sub panel where the two black wires are now connected in previous post pics. Gottcha !

Sounds easy enough, then I will test plugs as you state.

So now I can now add more breakers to the box, maybe change out the 20 amp ones to 10 amps each to get the 60 equivalent from my main breaker. right? I'll need more plugs now that i can rid my rack of the two power conditioners I have there.

Thanks Bob !! Correct me again if what I reiterated back is wrong.

Athanasios

PS any one want to buy a monster power and an adcom power conditioners? Very Happy

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