How to mount a shunt?
- Thread starter dmitrym
- Start date
iceledoar
Off Grid, Off Grid. Not even sometimes.
Always approach a shunt with caution, from the left side. Avoid direct eye contact and ever so quietly give praise. Then and only then may you attempt to mount. I normally, (unless I'm feeling a little wild) I carefully mount, first one side then the other.
I find a light appetizer (sea food platter, charcuterie, etc) is not a bad idea. Bottle of wine always help too. I may try quiet praise also. ?
RCinFLA
Solar Wizard
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- Jun 21, 2020
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I mounted my 500A/50mV shunt is a stock plastic electric outlet box, flat no outlet cover, with two 3/4" access for PVC conduit on either long ends. Drilled small hole in middle side to bring small shunt sense wires out. Small gauge for the sense wires act as their own fuse if shorted to opposite battery polarity.
Most folks do not realize how much heat can be generated by high current shunts. I do not recommend using the 75 mV shunts as they just increase the heat generated. Heat depends how long you run the high current for. I^2 x Rshunt.
Most folks do not realize how much heat can be generated by high current shunts. I do not recommend using the 75 mV shunts as they just increase the heat generated. Heat depends how long you run the high current for. I^2 x Rshunt.
Last edited:
Thunderstorm2011
New Member
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- Mar 27, 2020
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Simple solution. Small piece of wood 90° angle brackets
Thanks. I’m putting this all in a box though. I’m kinda wary of leaving a naked shunt. I’m thinking maybe small Tupperware and a double sided Velcro.
Thunderstorm2011
New Member
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The wires hold it in place
Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
Long time ago I came to the conclusion of using Deltec Shunts which have a phenolic backing / mounting which you can screw to a wall or whatever. A Shunt can generate heat and as such should be mounted so that the heat is a non issue (also increases resistance and that's not good).
The ironic thing is, there are Shunt Bases / Holders for sale that cost as much as a complete shunt !
Few idea's on how to make a base:
https://www.thingiverse.com/thing:3477529 (could make it with Plastic "stock")
A good idea here using an ABS Box (could even let the shunt free-float inside one if a cover is on it.
Couple of other ideas:
The ironic thing is, there are Shunt Bases / Holders for sale that cost as much as a complete shunt !
Few idea's on how to make a base:
https://www.thingiverse.com/thing:3477529 (could make it with Plastic "stock")
A good idea here using an ABS Box (could even let the shunt free-float inside one if a cover is on it.
How To Guide: Installing an Ammeter & Shunt
How To Guide: Installing An Ammeter & Shunt Introduction This is a guide to installing a simple cheap Ammeter as can be found on ebay sites. The guide is likely to be similar for any brand ammeter. Disclaimer This guide is intended to demonstrate how I installed the unit, following the instru...
www.canalworld.net
Couple of other ideas:
ianganderton
Auckland, NZ
What about something 3D printed?
You might be able to find a free STL file online and a public 3D printer, I’ve found some libraries in Australia and New Zealand have them
Search Thingiverse - Thingiverse
Download files and build them with your 3D printer, laser cutter, or CNC.
www.thingiverse.com
PHoganDive
Solar Enthusiast
As an earlier post mentioned, it is not a good idea to mount them in a small enclosed box, they can dissipate a significant amount of heat when passing large currents, you need to allow that heat to dissipate, not box it up. A 500 amp, 75 millivolt shunt will dissipate 37.5 watts of heat running at full capacity (500 x .075). If you boxed that up in that small plastic box, it would likely get hot enough to melt the plastic.Long time ago I came to the conclusion of using Deltec Shunts which have a phenolic backing / mounting which you can screw to a wall or whatever. A Shunt can generate heat and as such should be mounted so that the heat is a non issue (also increases resistance and that's not good).
The ironic thing is, there are Shunt Bases / Holders for sale that cost as much as a complete shunt !
Few idea's on how to make a base:
https://www.thingiverse.com/thing:3477529 (could make it with Plastic "stock")
A good idea here using an ABS Box (could even let the shunt free-float inside one if a cover is on it.
How To Guide: Installing an Ammeter & Shunt
How To Guide: Installing An Ammeter & Shunt Introduction This is a guide to installing a simple cheap Ammeter as can be found on ebay sites. The guide is likely to be similar for any brand ammeter. Disclaimer This guide is intended to demonstrate how I installed the unit, following the instru...www.canalworld.net
Couple of other ideas:
ianganderton
Auckland, NZ
I guess good venting in the box would solve that.
Most electronics need a pathway to dissipate heat
As you can see in post #27 I just used zip ties:
diysolarforum.com
48v LiFePO4 build
16 cells properly arranged. Now to make BMS cables since my 3/8 ring terminals arrived.
diysolarforum.com
Yep, you absolutely need big ventilation holes if you do that. But the best is just to let it in free air, it'll give more accurate results (those shunts aren't zero tempco resistors, only low tempco) and you don't risk melting plastic...
Also it's recommended to not go past 2/3 of the shunt rating, so for example if you want to measure 300 A max it's a lot better idea to use a 500 A shunt instead of a 300 A one.
Also it's recommended to not go past 2/3 of the shunt rating, so for example if you want to measure 300 A max it's a lot better idea to use a 500 A shunt instead of a 300 A one.
TheGriz
More Power Scottie!!!
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- Feb 17, 2020
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I cut a 1/2" piece of plywood roughly 1.5"x5". Then drilled four 3/16" holes in appropriate spots to use zip ties (pulled tight) to hold the shunt to the ply. Need to carve a small channel on back of ply so zip tie would be flush with ply. Then drilled two holes at each end for screws to mount to larger plywood where everything else is mounted.
Ampster
Renewable Energy Hobbyist
schmism
Solar Addict
Only durring mating seasonDoes it matter if it is a naked shunt?
Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
I run with Deltec 500A/50mv shunts, they do get "warm" but never HOT. Always derate of course, as mentioned above, by a minimum of 25% at least just to be on the safe side.
IF you have a Shunt that gets Hot to the touch IT IS UNDERRATED or you have a wiring fault at the Shunt like a bad crimp / lose connection. The Molded PVC boxes can handle up to 50C/122F temps and higher depending o class & type.
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