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Re: Power Watch, Progressive, Victron, Battle Born

Reply #25 – May 23, 2020, 07:38:26 pm

The original cables in your coach may have been 2/0 based on the size of inverter and charger size. And the length of the cables. You probably have a 3/0 cable from back in the engine compartment up to the main common post behind the white panel.

If you are using Battle Born batteries I would suggest upping cable size to 4/0 from the batteries (I would use a bus bar) to the common positive post behind the white panel and then to the big fuse and then 2 - 2/0 to the Multiplus

See wiring diagram in post# 20.

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Re: Power Watch, Progressive, Victron, Battle Born

Reply #26 – May 23, 2020, 07:45:11 pm

I agree ,as built,  risks were smaller. How much more energy is capable of being released with li-ion batteries?

All the makers warn of dead shorts. 

Side crash into the compartment?

Thousands of dollars in expensive parts to not use safer, possibly lower resistance tinned, non corrosive group three copper flexible cables?

$100?  The batteries and inverter are right next to each other.

If memory serves me there were 2 different sizes in 4/0?

Not sure on the marine UL 1426. 

Not my business whether anyone uses this or not. 

Hard to be too safe.  As a brag point you would impress anyone.

As a selling point it would add credence to the engineering would it not.

But it is a few dollars more.

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Re: Power Watch, Progressive, Victron, Battle Born

Reply #27 – May 23, 2020, 08:54:05 pm

CoastalBuilder,

In your application a high quality fine stranded EPDM welding cable will work fine, be fire retardant and meet the same UL requirements for wire safety as PVC covered cable.

Bob believes PVC jacketed cable is better.  Maybe more fire retardant? I respect his fire concern and he can choose the cable that fits his needs in his coach when he replaces all of his cables.

PCV covered cable is sometimes used in new RVs now because it is cheaper.  Maybe not if you are using marine grade tinned PVC cable but that is not what the RV builders are using.

But quality EPDM welding cables you buy today are also flame retardant.

When a lot of bends are required to complete the wiring of an application, welding cable is often preferred due to its flexibility. The flexibility of welding cable is a result of its construction using finer strands of copper and EPDM insulation. Because of the finer copper strands, the amount of copper per foot is greater in welding cable than battery cable, which allows welding cable to handle higher voltage applications.

EPDM welding cable resists grease, oil, and water, as well as protecting against abrasion, cuts and tears. However, welding cable is also flame resistant and meets the UL-1581 standards. This UL rating gives it an edge on battery cable when it comes to protection from the elements.

EPDM Welding cable is ideal for installations with exposure to colder weather because of its construction with thinner stranding which allows increased flexibility and usability.

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Re: Power Watch, Progressive, Victron, Battle Born

Reply #28 – May 23, 2020, 10:58:26 pm

the amount of potential energy that you're going to be pulling from those batteries leads me to say that you should if not must use 4/0 cable. I would use marine cable tinned. But welding cable would be sufficient as well. The small price to pay now. if you try to pull too many amps through two small of a  cable it's going to generate heat. generate too much heat it's going to melt.
Otherwise glad you are keeping the coach and looking forward to seeing your lithium install.

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Re: Power Watch, Progressive, Victron, Battle Born

Reply #29 – May 24, 2020, 12:01:41 am

Yes some kinds af epdm have formulas that are fire redardent. Expensive and rare.  Are you willing to bet the welding cable MAY be fire retardent.  Unless identified as such I would be suspicious.

Versus labeled cabling.

To save $50 difference on a many CB system.

Are you all that frugal? 

"Well it never gave me no problem." 

Changing the amount of amp around the coach versus the oem wiring.

Probably capable of many times the amps if a failure occurs?

I'd like to think this has not happened to me a few times as a Foretravel sales manager.

Hence the above quote.  Did I hear this here?

Take this as an advantage in a optimized low idle amp power consumption system.

Wanna' bet if you went to tinned tiny stranded group three cabling you would pick up the power lost per foot from the higher resistance cabling.  Every cable has a loss per foot number.

Heats the cable. Stealing from your systems capacity and charge rates.

Any of you ever checked your cable temps?  I bet not.

Every degree over ambient is suppling your energy to heat a wire.

Yet you would use more resistant non retardant cabling?

This is like old Foretravel days.  This is great.  Convince me..

Less expensive does not cut it normally in my rv experience.

The same exact quality for less money is great.  Less money. Less quality? Not me. 

Been there

 

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Re: Power Watch, Progressive, Victron, Battle Born

Reply #30 – May 24, 2020, 06:55:09 am

Quote from: Caflashbob – May 24, 2020, 12:01:41 am

This is great. 

Far from it.

Mike

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Re: Power Watch, Progressive, Victron, Battle Born

Reply #31 – May 24, 2020, 09:20:23 am

For others, down the road that may be reading this.  Here is the TEMCo welding cable specs.  Thank you all for the comments.

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Re: Power Watch, Progressive, Victron, Battle Born

Reply #32 – May 24, 2020, 09:29:27 am

OK, please, lets "agree to disagree" and move on.

This discussion/argument is appearing in way too many threads-- most unrelated to the original topic.

Both sides have been well discussed. 

PLEASE REFRAIN FROM INJECTING IT AGAIN INTO THIS OR ANOTHER THREAD! They will be deleted.

THANKS.

Brett/moderator

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Re: Power Watch, Progressive, Victron, Battle Born

Reply #33 – August 22, 2020, 06:08:48 pm

So.... I'm finally knee deep in making this change.  The old batteries weigh 1,200 each.  At least that is what my back says.  One negative terminal post was loose and and another one was broken.  These really, really needed changed out.  No date code punched on them so I have no idea how old they were.  One quick question - Doe the Multiplus E (T sense) - wire go to the bus bar, to a battery - terminal or to the down stream side of the shunt?  Other than praying it all works that is my big question right now.  Thank you!

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Re: Power Watch, Progressive, Victron, Battle Born

Reply #34 – August 22, 2020, 07:20:29 pm

I would say that the temperature sense goes to the negative terminal of the battery

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Re: Power Watch, Progressive, Victron, Battle Born

Reply #35 – August 22, 2020, 11:24:45 pm

 From the Multiplus manual ...
4.4.3 Temperature Sensor
The temperature sensor supplied with the product may be used for temperature-compensated charging (see Appendix A). The sensor is isolated and must be mounted on the batteries minus pole.

If you are also installing a Victron BMV 702 or 712 with the optional temperature sensor it goes to the PLUS battery terminal

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