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Disconnect Boxes and Breakers => E Panel's, Disconnect Boxes and Breakers => Topic started by: TomW on November 21, 2012, 10:33:15 AM

Title: Epanel 500 Amp shunt and a Doc Wattson?
Post by: TomW on November 21, 2012, 10:33:15 AM
I have just installed an Epanel for our FX2524 inverter and a Midnite Classic 150. The Epanel comes with an install 500 amp 50 millivolt shunt. I have been using a couple Doc Wattsons to monitore my incoming power on wind and solar for years.

I read that you can modify the Doc to use an external shunt but cannot seem to find the information on the shunt requirements to do that. Just curious if the included shunt on the Epanel would be appropriate for the external shunt?

I am squirming around trying to get some monitoring back in the system since I upgraded to the Epanel.  I like watching analog meters do their thing but I appreciate having data over time I can see.

Maybe there is a device made for doing what I want with that Epanel shunt in the battery negative lead? Any ideas appreciated.

Thanks.

Tom

Got the solar upgrade installed yesterday ;D  Sorry I just love looking at these:

(http://pics.ww.com/d/461538-2/100_5409.JPG)
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: Nashville on December 22, 2012, 10:26:30 PM
Nice set-up! Is it stationary or tracking?
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: Vic on December 22, 2012, 11:23:51 PM
Hi Tom,

YES,  a very nice looking installation indeed.

Am sure that you are a capable searcher on the Net,  but,  have you studied this (?):

http://www.rc-electronics-usa.com/special-mods.html

A 500 A shunt is bodacious,  but fairly common for DC Conduit boxes and panels.

Have Fun,  Best Wishes for the Holidays and the New Year, Vic
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: Halfcrazy on December 23, 2012, 06:40:51 AM
Tom
We also should have the first revision of Current Sense Modules for the Classic in about 4-6 weeks. You will make a great Beta tester for one as you are reading the ModBus so that will be a huge help.

Ryan
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: TomW on December 23, 2012, 10:39:54 AM
Quote from: Halfcrazy on December 23, 2012, 06:40:51 AM
Tom
We also should have the first revision of Current Sense Modules for the Classic in about 4-6 weeks. You will make a great Beta tester for one as you are reading the ModBus so that will be a huge help.

Ryan

OK, can't wait.

Will it sense current through the E-panel shunt or some other mechanism?
Always up to trying new stuff.

Tom
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: dbcollen on December 23, 2012, 12:35:55 PM
Tom,

I just found a few 100a shunts in my parts drawer if you need one for your doc watson conversion.
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: TomW on December 23, 2012, 01:17:07 PM
Quote from: dbcollen on December 23, 2012, 12:35:55 PM
Tom,

I just found a few 100a shunts in my parts drawer if you need one for your doc watson conversion.

db;

Might take you up on that later this winter. Not sure I have enough oomph in a soldering iron to unsolder the internal shunt.

Catch you in IRC to work out any details.

Thanks.

Tom
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: Halfcrazy on December 23, 2012, 03:01:20 PM
It will monitor the Shunt in the epanel or any comparable shunt for that matter and report it back to the Classic
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: TomW on December 23, 2012, 03:24:54 PM
Quote from: Halfcrazy on December 23, 2012, 03:01:20 PM
It will monitor the Shunt in the epanel or any comparable shunt for that matter and report it back to the Classic

Ryan;

Now you opened a can of worms....

Will it support multiple sources? That would be a nifty, useful feature.

Sorry, feature greed is a sickness I seem to suffer from.

Tom
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: Halfcrazy on December 23, 2012, 03:29:58 PM
Well it actually bolts onto the shunt so it will support a single shunt. So a single Classic will support a single MNCSM (current sense module).



Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: TomW on December 23, 2012, 03:36:34 PM
Quote from: Halfcrazy on December 23, 2012, 03:29:58 PM
Well it actually bolts onto the shunt so it will support a single shunt. So a single Classic will support a single MNCSM (current sense module).

Ryan;

Aw, well I guess that is a good V1.  ;D :-X

I do like the Midnite MN... naming convention.

Tom
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: Halfcrazy on December 23, 2012, 03:43:27 PM
Yes we have another product in the fire now that will be pretty cool. It will be mulit Channel and speak ModBus. It will have Ethernet and rs232. I do not want to leak to much but it will be a very very powerful and useful device for not much money.


Ryan
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: TomW on December 23, 2012, 04:24:01 PM
Ryan;

No offense but don't you have a life outside Midnite Solar? I see you on here on weekends when most folks are doing recreational stuff. Don't get me wrong it makes for an excellent reputation for online support! I just don't have any ambition in the winter so I spend time bugging folks online.


Anyway, I get the "playing it close to the vest" but just hate to wait cuz I know whatever you come up with will be cool stuff.

Monitoring and logging is one of my addictions. And why I have a pile of unused and / or dead devices like Linksys Slugs, Guru plugs & Cai Webcontrol boards here.

Maybe one of the former Outback guys could explain why when I power down a computer that monitors the Mate via a USB to serial cable it shuts off the FX? That has frustrated attempts to monitor the Outback gear that way for a couple years. Sorry that is topic drift on a competitors products but I did not get much help from official sources ....

Tom
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: Volvo Farmer on December 24, 2012, 09:46:34 AM
Am I correct in assuming that this MNCSM will allow me to end absorb with the actual amps flowing into the battery, irrespective of loads on the system?

If so, put me on the list of people to notify when they become available, because I want one!
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: Halfcrazy on December 24, 2012, 11:49:00 AM
Yes you are absolutely spot on. The MNCSM will allow that Classic to end its absorb charge based on End Amps but the TRUE end amps.


Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: dgd on March 20, 2013, 05:51:48 PM
Quote from: Halfcrazy on December 23, 2012, 06:40:51 AM
Tom
We also should have the first revision of Current Sense Modules for the Classic in about 4-6 weeks. You will make a great Beta tester for one as you are reading the ModBus so that will be a huge help.

Ryan

How is this CSM development progressing? Any indication of when it will be available?

dgd
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: boB on March 20, 2013, 08:22:11 PM
Quote from: dgd on March 20, 2013, 05:51:48 PM
Quote from: Halfcrazy on December 23, 2012, 06:40:51 AM
Tom
We also should have the first revision of Current Sense Modules for the Classic in about 4-6 weeks. You will make a great Beta tester for one as you are reading the ModBus so that will be a huge help.

Ryan

How is this CSM development progressing? Any indication of when it will be available?

dgd


It's going very well !

I really shouldn't give any dates, but probably still 3 months out...  Just because of the typical red tape in getting new products out.

I think you're gonna love this !  Looks like it is going to be very accurate too.

boB

Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: Halfcrazy on March 21, 2013, 05:15:15 AM
We should of course have a special group of Alpha Testers on this product so feel free to bug me via Email or PM here for that

Ryan
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: SolarMusher on March 21, 2013, 07:08:40 AM
Email sent.
Erik
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: TomW on March 21, 2013, 10:59:11 AM
Quote from: Halfcrazy on March 21, 2013, 05:15:15 AM
We should of course have a special group of Alpha Testers on this product so feel free to bug me via Email or PM here for that

Ryan

Ryan;

You know I am in.

Tom
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: Resthome on March 22, 2013, 01:44:44 AM
Quote from: Halfcrazy on March 21, 2013, 05:15:15 AM
We should of course have a special group of Alpha Testers on this product so feel free to bug me via Email or PM here for that

Ryan
Be glad to participate, Ryan.
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: Andrejs on March 22, 2013, 05:51:47 AM
Quote from: Halfcrazy on March 21, 2013, 05:15:15 AM
We should of course have a special group of Alpha Testers on this product so feel free to bug me via Email or PM here for that

Ryan

... and I would be interested as well!

Andrejs
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: Vern Faulkner on March 22, 2013, 06:19:54 PM
Quote from: Halfcrazy on March 21, 2013, 05:15:15 AM
We should of course have a special group of Alpha Testers on this product so feel free to bug me via Email or PM here for that

Ryan

What's the worst that could happen?

I'm in, if needed.
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: dgd on March 22, 2013, 07:17:14 PM
So what are  main features of this current monitor?
- resides close to a 50mv 500A shunt,  what about other shunt options?
-16bit A to D to give at least 0.1A accuracy over +400A to -400A
-cpu included to do modbus (ugh!) interface via serial or ethernet
-MNGP can be wired in to provide lcd + rubber button interface
-MNGP on a Classic can see it and report
-basis for a battery monitor
-a web interface
-a new firmware release for the Classic to use data from this monitor or monitors
-perhaps get a more accurate battery voltage measurement too
-maybe deal with a 150A shunt for Classic input and report accurate A and V
-Classic ignores its builtin Amps/Volts measurements for input and battery, and followme A and V  from monitor
-aux alarm output if current extraction from battery exceeds a configured limit, relay control
-surge events recorded - logging 380 days

dgd
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: SolarMusher on March 23, 2013, 02:38:24 PM
Quote from: Halfcrazy on December 24, 2012, 11:49:00 AM
Yes you are absolutely spot on. The MNCSM will allow that Classic to end its absorb charge based on End Amps but the TRUE end amps.
HI Ryan,
Could the CSM be mounted on the same shunt that is already used by a Magnum BMK or does it needs its own shunt?
Erik
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: boB on March 23, 2013, 07:56:51 PM
Quote from: SolarMusher on March 23, 2013, 02:38:24 PM
Quote from: Halfcrazy on December 24, 2012, 11:49:00 AM
Yes you are absolutely spot on. The MNCSM will allow that Classic to end its absorb charge based on End Amps but the TRUE end amps.
HI Ryan,
Could the CSM be mounted on the same shunt that is already used by a Magnum BMK or does it needs its own shunt?
Erik


That's a great question that I had not thought of but I'm not sure it would matter ?

It is a local voltage developed across the shunt and read across the shunt so I bet it would
work.  I won't bet my life on it, but I think it might just work.

boB

Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: boB on March 23, 2013, 08:05:25 PM
Quote from: dgd on March 22, 2013, 07:17:14 PM
So what are  main features of this current monitor?
- resides close to a 50mv 500A shunt,  what about other shunt options?
-16bit A to D to give at least 0.1A accuracy over +400A to -400A
-cpu included to do modbus (ugh!) interface via serial or ethernet
-MNGP can be wired in to provide lcd + rubber button interface
-MNGP on a Classic can see it and report
-basis for a battery monitor
-a web interface
-a new firmware release for the Classic to use data from this monitor or monitors
-perhaps get a more accurate battery voltage measurement too
-maybe deal with a 150A shunt for Classic input and report accurate A and V
-Classic ignores its builtin Amps/Volts measurements for input and battery, and followme A and V  from monitor
-aux alarm output if current extraction from battery exceeds a configured limit, relay control
-surge events recorded - logging 380 days

dgd


Since ths MN shunt monitor just tells the Classic what it is reading through the Aux 2 terminals,
most all of the software/firmware is done in the Classic itself so I believe most if not ALL of
your list will have a very good chance of being implemented.

And on the voltage accuracy from the Classic itself, this is going to be done using a calibration
table for just that purpose so that will also be addressed.  The Classic is already modbus (yech
for you) so that is happening and of course the web interface so you should get all of that too.
Not sure about a 150A shunt, but that ~could~ of course be done with a simple re-calculation.
The hard part about using non-standard shunts is that the distance between screws are
different than the 500A/50mV shunts and so you would have to run a wire or a piece of copper
from one of the CSM screw hole pads to one of the different shunt screws.  Otherwise it should
be pretty easy for that to work as well.  Same modification for a 1000A/1000mV shunt which
are larger than the 500A/50mV shunts.

And yes, of course, 0.1 amp resolution with +- 0.05 amp accuracy.   Actually, I think it may
be slightly better than this from what I am seeing so far.

boB
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: SolarMusher on March 24, 2013, 07:30:42 AM
Quote from: boB on March 23, 2013, 07:56:51 PM
Quote from: SolarMusher on March 23, 2013, 02:38:24 PM
Quote from: Halfcrazy on December 24, 2012, 11:49:00 AM
Yes you are absolutely spot on. The MNCSM will allow that Classic to end its absorb charge based on End Amps but the TRUE end amps.
HI Ryan,
Could the CSM be mounted on the same shunt that is already used by a Magnum BMK or does it needs its own shunt?
Erik

That's a great question that I had not thought of but I'm not sure it would matter ?

It is a local voltage developed across the shunt and read across the shunt so I bet it would
work.  I won't bet my life on it, but I think it might just work.

boB
Hi boB,
Ok I will try it this way, it would be great if one could use it also as an upgrade into an existing Classic.
How will you want to sell it? As an integrated or a "stand alone" MNBCM part?
Erik
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: boB on March 24, 2013, 04:57:32 PM
Quote from: SolarMusher on March 24, 2013, 07:30:42 AM

How will you want to sell it? As an integrated or a "stand alone" MNBCM part?
Erik

I'm pretty sure it will be sold as a circuit board and plastic cover kit with instructions
in a cardboard box.

boB
Title: Re: Epanel 500 Amp shunt and a Doc Wattson?
Post by: SolarMusher on March 24, 2013, 06:25:35 PM
QuoteI'm pretty sure it will be sold as a circuit board and plastic cover kit with instructions
in a cardboard box.
Great, thanks boB.