New Hisun sector E1 cables melting

[Dafna Brown]

My father in law just delivered our new sector E1 and after 5 minutes of driving around we smelled burning smoke and discovered the three wires red, yellow and green were burning. 
It still drives but were afraid of it catching on fire!

Anyone else have this experience? 

[Travis]

that definitely is not good.. before you touch anything, call the place you bought it from and tell them what happened.

 

[cliffyk]

Got any photos, each is worth 1k words...

[Dafna Brown]

Here’s a photo of the melted cables. We were very lucky to have stopped driving when we saw smoke. Apparently, another Sector E-1, while on a test drive did catch  on fire! Those  people were able to jump off safely before it burned to the ground. 

[EVSupport]

heat like this is normally caused by connections not being tight, or even the crimp terminal not being properly crimped. The heat comes from the resistance on the connection.  With the ign turned off remove the cover and check the tightness of the nuts.

 

[Dafna Brown]

Thanks! 

[EVSupport]

But the cables have lost the insulation , looks like its fallen away, so ultimately the cable will need to be replaced.  If it was loose connections or crimps that can be re done, then the cables should be cleaned up and a double layer of heat shrink sleeve put over the melted section. Never run these with bare cable.

 

[cliffyk]

This is a manufacturing defect...

The cable is clearly marked as being 50 mm², equivalent to  AWG 1  cable:

The maximum allowable ampacity of 50 mm² cable is 110 A @ 140° F--however in continuous duty that capacity should be downgraded to 100  A, throw in a crimped terminal and your down to 85 A  or so.

The Sector E1 motor is claimed to be 27 HP which is 20.14 kW (27 *0.746). At 48 V in a single phase  system  it  would  require 419.6 A to deliver 20.14 kW--however as this a 3 phase motor each conductor needs to carry just  1/3rd of that 419.6 A.. Or,  ≈ 140 A

I.e. the cables are undersized, Copper is expensive and someone cut manufacturing costs in the wrong place...

[Dafna Brown]

Wow! Thanks for the thorough explanation. Sounds like Hisun is completely irresponsible... or lacks QA at best.  Now, the question is: do you ask Hisun to fix the unit or return it and buy something else?

[EVSupport]

50mm 2 cable is adequate for the E1 . Rangers use slightly smaller cable size and many mainstream EVs use 50mm2 for the motor cables. You would need max power for some hours to get the cabling warm, let alone so hot as to melt the outer. As its happened in one location and high resistance would cause the localised heating that has to be the cause. I have owned and work on EVs for my income for the last 10 years. 50mm2 is adequate, for this use. The vehicle does not produce a constant 20+kw its a peak power output, if it did you would be working it continuously under full load,  The motors are rated at under 7kw at continuous use  under normal usage.  At  continuous 20kw use the motor and sevcon would have been cutting back due to over heating.  Just to say the cable is undersized is to misunderstand how its used and how the vehicle functions., and the motor / controller specifications.

It could also be a motor cabling fault at the junction with the three feed cables.  Hisun really need to investigate this properly.  The cable size has not been cut its always been the same. I have worked on a few early E1s and they are the same. Some have already been through two sets of batteries prior to coming to me for Li Ion conversions. None have had this problem. The cable from the Sevcon controller to the pack is the same size cable and if it were undersized then that would have been the first section to get hot and fail. 

On the Polaris rangers which I have been in for Li ion conversions, thats so far about 17, which have the higher power Sevcon controller and higher power motor than the E1, none have had fault due to cable sizing . The ranger motor (I just looked ) is rated at 8.5kw and is higher power than the hisun E1.

50mm2 is  in between AWG 1 and 0  its larger than 1 (approx 42mm2) and smaller than 0 (approx 53mm2)

[cliffyk]

8 hours ago, EVSupport said:

50mm 2 cable is adequate for the E1 . Rangers use slightly smaller cable size and many mainstream EVs use 50mm2 for the motor cables. You would need max power for some hours to get the cabling warm, let alone so hot as to melt the outer. As its happened in one location and high resistance would cause the localised heating that has to be the cause. I have owned and work on EVs for my income for the last 10 years. 50mm2 is adequate, for this use. The vehicle does not produce a constant 20+kw its a peak power output, if it did you would be working it continuously under full load,  The motors are rated at under 7kw at continuous use  under normal usage.  At  continuous 20kw use the motor and sevcon would have been cutting back due to over heating.  Just to say the cable is undersized is to misunderstand how its used and how the vehicle functions., and the motor / controller specifications.

It could also be a motor cabling fault at the junction with the three feed cables.  Hisun really need to investigate this properly.  The cable size has not been cut its always been the same. I have worked on a few early E1s and they are the same. Some have already been through two sets of batteries prior to coming to me for Li Ion conversions. None have had this problem. The cable from the Sevcon controller to the pack is the same size cable and if it were undersized then that would have been the first section to get hot and fail. 

On the Polaris rangers which I have been in for Li ion conversions, thats so far about 17, which have the higher power Sevcon controller and higher power motor than the E1, none have had fault due to cable sizing . The ranger motor (I just looked ) is rated at 8.5kw and is higher power than the hisun E1.

50mm2 is  in between AWG 1 and 0  its larger than 1 (approx 42mm2) and smaller than 0 (approx 53mm2)

All quite accurate, however in this instance the 50  mm² cable  and/or  the manner in which the terminals were attached were inadequate to their task. Also, sizing of cables with less than 50 % of potential full-load capacity--then relying on a "normal usage"  factor to save your butt--is hardly sound engineering.; an d again in this instance created a significant hazard.

They should be sized for at least 80% of maximum load; however in the OP's case it looks as though the terminations were not properly crimped leading to excessive resistance...

[Dafna Brown]

What electric UTV would you recommend? 

[cliffyk]

1 hour ago, Dafna Brown said:

What electric UTV would you recommend? 

None, nor electric cars. It is an industry in it's infancy that needs time to mature. Electricity is not an energy source it needs to be generated from energy sources--currently in the civilized world a modestly inefficient process to create AC current, we  then carry it, with losses, over power lines to it's application  where in the case of electric vehicles we convert it to DC--with losses-to charge batteries to convert that stored energy to motive force (with losses) Direct conversion of an energy source (gasoline) to motive force is modestly inefficient but still in the overall more efficient than all the conversion and transmission loses. In any valid "Well to Wheels" analysis, modern ICE's win every time...

[EVSupport]

7 hours ago, Dafna Brown said:

What electric UTV would you recommend? 

Its down to use, here in the UK virtually all UTVs are used in a commercial or farming use, few are for personal/ leisure use. We dont have access to trails etc. So the increasing use of Electric UTVs is in a more professional way, here the land owners are willing to shift from fossil fuels and many have their own Solar or wind turbines. It all looks good shifting to a lower carbon business. My work on UTvs is mainly on Polaris Rangers , converting to Li ion, the costs stack up when you are using a set of lead every 18months which many do.  The weight reduction is well over 150kg, and the same on the HisunE1. Here we are seeing a much bigger gain over the original batteries. My own view is the E1 originals are not big enough in capacity and they suffer from higher degradation as a resultunder tough use, but ok at a low / domestic level.  In the UK a Ranger is around £14k  a Hisun E1 around £9k. Thats a big difference. Now seeing some older E1s and they have taken some serious abuse, and still work well. The one I am currently converting , had been pressure washed  before it came in. I then strip the sides off and pressure wash again, then I take out the old batteries, and drop the under pans, and pressure wash again. In all I would guess we got about 10 std buckets of mud out. Thats a lot of weight.  The propshaft was not visible under the front floor. It was solid with crud. But still it worked.  On the Li ion front I cant get as much into the E1 chassis space as the ranger.  But its lighter and the suspension is brilliant.  For users here its down to cost. I personally believe the Ranger and the E1 are as capable as each other, I like the ranger being slightly bigger.

With Evs the old arguments about power generation losses etc are all out there. But remember the energy used to convert a gallon of gas from crude oil will take a road going EV around 28 miles. Thats before burning the Gas. WIth more and more localised power generation,  from Solar and Wind the grid losses are much less of an issue. Especially when you generate the power your self, perhaps with your own storage.

Here in the UK we have shifted away from Coal , as certain US presidents have discouraged, we now have a very high % of renewables providing our power. The last coal fired power stations have now closed. So the so called long tail pipe argument is no longer a vaild one.  Thats very different in the US where renewables are still not dominant. That will change. In 10 years this discussion wont be taking place.

There is also the pleasure of not having a noisy smelly power unit beneath you, and the knowledge that your efforts are making a difference to not only your environment, but the environment of all of us.

[Osney]

On 7/26/2021 at 3:36 AM, cliffyk said:

None, nor electric cars. It is an industry in it's infancy that needs time to mature. Electricity is not an energy source it needs to be generated from energy sources--currently in the civilized world a modestly inefficient process to create AC current, we  then carry it, with losses, over power lines to it's application  where in the case of electric vehicles we convert it to DC--with losses-to charge batteries to convert that stored energy to motive force (with losses) Direct conversion of an energy source (gasoline) to motive force is modestly inefficient but still in the overall more efficient than all the conversion and transmission loses. In any valid "Well to Wheels" analysis, modern ICE's win every time...

Without stirring up too much of a hornet's nest here, I'd suggest you look into the energy costs and losses involved in getting your gasoline from out of the ground and into your tank. Yes, the modern EV industry is in its infancy, and still too much of our worldwide electricity generation relies on burning fossil fuels, but electric powered vehicles pre-date the internal combustion engine and the engineering involved is very well understood.

[EVSupport]

Any update on this?

[Richard Heyman]

I, too, am interested in how this issue gets resolved.

I also want to highlight some of the benefits/versatility (at least for me) using a solar/electric UTV (Hisun Sector E1):

I traveled deep into public lands in New Mexico with a high-efficiency electric refrigerator (store food/game) and electric skillet (no open flames for cooking).

The Hisun also powers a cabin entirely or as an augmented source when needed.

I plan to replace all the lead-acid batteries with LiFePo4 batteries. I have already done so for the cabin with very good results.

 

[Travis]

Wait a minute....... Solar panel on top of your machine? that's a pretty dang good idea!

 Keeps more sun off of you too.