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Makes And Models => Zero Motorcycles Forum | 2013+ => Topic started by: Killroy on June 25, 2018, 05:21:40 AM

Title: Another Melted 120V Charge Cable
Post by: Killroy on June 25, 2018, 05:21:40 AM
Yes, another partially melted 120V Charge Cable. 

let's go through the normal checklist for this common problem:
--14 AWG, 5-6 ft - check
--Normally unplug at wall outlet - check
--The conductors on the cable and the Zero look clean- check
--The cables and heat shrink on the the Zero behind the C14 plug look good.  This part has been replaced/repaired before by Zero when a previous cable was melted.  - check
--The stock onboard charger was replaced by the dealer under warranty ~6 months ago. 

I have not checked the what the wall outlet contacts or voltage.  The charge cable was worryingly warm at both ends the last time I unplugged it at the wall before charging tapered.  A little white plastic internal to the plug had melted and the plug conductors are bent a little from the weight of the cable hanging from the wall.  The cable is probably a extra one that I bought from Amazon, but 14 AWG is embossed on it. 

I hope its is not the new onboard charger, but that is what I suspect because it seemed that the last onboard burnt the last cable I had when it failed.

Title: Re: Another Melted 120V Charge Cable
Post by: rayivers on June 25, 2018, 06:21:01 AM
Here's two more absolutely critical items for your checklist:

- all cable/receptacle contacts in intimate/tight contact with each other (firm push fit, not it-doesn't-feel-loose semi tight)
- all wire-to-contact connections as perfect as possible (clean copper crimped tight to clean terminal, then soldered & heat-shrinked)

All low-friction and/or high-resistance interfaces will quickly get hot, sometimes real hot.  At some point arcing may occur in the metal parts, causing carbon buildup and even higher resistance & heat.  If the plastic soften or melts, the contacts will move relative to each other and likely loosen up or twist.

I always squeeze female contacts together if possible to increase their tightness, and spread 2-layer male contacts apart for the same reason. If problems persist, I'll make my own power cables using quality Hubbell-type plug ends, with screw terminals and oversized brass contacts.  Even Home Depot 2-piece plug ends on 12 ga. or 14 ga. cable will often be way better than a generic no-name cord.  And Deoxit is amazing.  :)
Title: Re: Another Melted 120V Charge Cable
Post by: Erasmo on June 25, 2018, 01:14:07 PM
Step 1 is to check your voltage on the wall.
Title: Re: Another Melted 120V Charge Cable
Post by: rayivers on June 25, 2018, 06:19:13 PM
Quote
Step 1 is to check your voltage on the wall.

+1. If it's low it's a bit expensive to reliably increase at high power levels, but always good to know.

These (https://www.amazon.com/Yeeco-Voltmeter-Measuring-Monitoring-Measurement/dp/B00PBW5A4I/ref=sr_1_3?ie=UTF8&qid=1529928444&sr=8-3&keywords=ac+voltage+meter) are cool, even though they often bear bad news at Rancho Ray. :) I have 4 of them.
Title: Re: Another Melted 120V Charge Cable
Post by: Richard230 on June 25, 2018, 07:39:47 PM
Step 1 is to check your voltage on the wall.

I have always wondered why my "110V" home electrical outlet shows 123V (which drops to 118V when plugged into my Zero's charger) on an AC voltmeter.   ???  Is someone using that word "nominal" again?  ::)
Title: Re: Another Melted 120V Charge Cable
Post by: MrDude_1 on June 25, 2018, 08:49:39 PM
Step 1 is to check your voltage on the wall.

I have always wondered why my "110V" home electrical outlet shows 123V (which drops to 118V when plugged into my Zero's charger) on an AC voltmeter.   ???  Is someone using that word "nominal" again?  ::)

its actually supposed to be 120 V nominal voltage +-6% for residential homes as measured on the inlet feed for the house.
Your house may further drop voltage if its wiring runs are long and small with heavy loads on them.
realistically I have never measured below 108v and I have seen 124v in areas with lots of grid tie solar.
Most devices work on 90-140 for US power, or 85-260 for universal input power. so its not much of an issue. the voltage is always dependant upon where you measure it, its not constant.
the frequency however, should be fairly accurate... but we dont really care about that for our DC powered electronics. (other than the PFC circuits)
Title: Re: Another Melted 120V Charge Cable
Post by: MrDude_1 on June 25, 2018, 08:54:03 PM
Quote
I have always wondered why my "110V" home electrical outlet shows 123V (which drops to 118V when plugged into my Zero's charger) on an AC voltmeter.

That happens all over my house, and is a major reason I got the voltmeters.  AFAIK 110VAC in homes hasn't been around since the 1950's, as voltages have crept up to facilitate moving more power through the same distribution wires / transformers.  The drop from 123V to 118V is caused by wire resistance, which can be considerable as many homes are wired with the smallest-gauge wire that will pass local codes.  I've seen my garage outlets go from 119V to 109V under a 20A load, which tells me the wiring used has 0.5 ohms total resistance (probably 18 ga.).

actually.... that tells me you need to go over to your breaker box and make sure the wire connections are tight... if they are, then pull that breaker off and check the contacts and bus bar for corrosion.  a 10v drop from a small 20a load means you have found a large problem. House circuits are ridiculously oversized compared to automotive wire sizing... and assuming you're in the USA, your 15A circuit should have 14ga, and if its a 20A circuit it should have 12ga.  These are all solid wire sizing, add 2 if you're using stranded (but you shouldnt be using stranded for a house)
Title: Re: Another Melted 120V Charge Cable
Post by: rayivers on June 25, 2018, 09:07:14 PM
I put in the new 20A breaker & outlet (not the wire), so everything's clean & wicked tight.  AWG 18 copper wire has a resistance of 0.0064 ohms per foot, and the total wire run's about 80-100 feet give or take, so @ 0.5 ohm total is close enough.  I have to deal with what's actually IN my house, not what should be in it. :)
Title: Re: Another Melted 120V Charge Cable
Post by: MrDude_1 on June 25, 2018, 10:20:20 PM
I put in the new 20A breaker & outlet (not the wire), so everything's clean & wicked tight.  AWG 18 copper wire has a resistance of 0.0064 ohms per foot, and the total wire run's about 80-100 feet give or take, so @ 0.5 ohm total is close enough.  I have to deal with what's actually IN my house, not what should be in it. :)

If you have 18ga wire in your house, you should not have a 20a breaker on that circuit. Even if it is only for one outlet.
ESPECIALLY if you are doing sustained high amp draws on it... any of that wire that is buried in insulation could easily overheat in that case.


And you dont have to deal with what is actually in your house, if its really your house you can change it. :)
Title: Re: Another Melted 120V Charge Cable
Post by: rayivers on June 25, 2018, 10:56:55 PM
Guess we'll just have to agree to disagree on this one.  I know the actual situation here, my actual usage, and the actual numbers involved, whereas you do not.
Title: Re: Another Melted 120V Charge Cable
Post by: Killroy on June 26, 2018, 02:38:07 AM
Step 1 is to check your voltage on the wall.

Voltage at the wall is 119 to 120 V without anything plugged in. 
Title: Re: Another Melted 120V Charge Cable
Post by: nedfunnell on June 27, 2018, 12:00:08 AM
Step 1 is to check your voltage on the wall.

Voltage at the wall is 119 to 120 V without anything plugged in.

Can you check the voltage with a load on it, either the bike charging (if it's possible) or something 1000 watts and up, like a space heater? If there's a significant drop, it could indicate a wiring issue.

I was able to locate a 12ga C13 cable through my BIL that works in IT. It's nice to have something a bit heavier duty.
Title: Re: Another Melted 120V Charge Cable
Post by: Doug S on June 27, 2018, 01:02:46 AM
I've seen my garage outlets go from 119V to 109V under a 20A load, which tells me the wiring used has 0.5 ohms total resistance (probably 18 ga.).

It's not just wire resistance that will cause the line voltage to drop under load. As MrDude says, contact resistance can play a big part, especially in older buildings. But there's also some drop in the transformer that services your house. It may not seem like a 10A load will cause much drop on a transformer that's rated for 200A, but most houses are serviced in a "split-phase" configuration, and a 10A draw from one of the phases can cause the system to re-stabilize at a slightly different point. The phase with the new load on it may drop a bit, with the other phase rising a bit.

Also, residential voltage hasn't (intentionally) changed since very early on. Drops in voltage from the nominal value are almost as damaging as rises -- AC synchronous motors overheat when underdriven -- and 60 cycles has been the standard in the US since Tesla won the AC/DC argument with Edison. What you will find is that the voltage in newly-built neighborhoods runs pretty hot at first, but drops as the neighborhood gets built out and loading on the transformers increases. If it drops too much, the power company will come out and change the taps on the transformer to bring it back in range, but that doesn't happen much in an established neighborhood.
Title: Re: Another Melted 120V Charge Cable
Post by: BamBam on June 27, 2018, 01:14:48 AM
Is that a 12ga 5-15P to C13 power cord (similar to the one that comes with the bike) you are referring to?  If so, please let us know where we can source such a cord.  The heaviest I've seen these cords is 14ga.
Title: Re: Another Melted 120V Charge Cable
Post by: Killroy on June 27, 2018, 03:52:05 AM
Step 1 is to check your voltage on the wall.

Voltage at the wall is 119 to 120 V without anything plugged in.

Can you check the voltage with a load on it, either the bike charging (if it's possible) or something 1000 watts and up, like a space heater? If there's a significant drop, it could indicate a wiring issue.

I was able to locate a 12ga C13 cable through my BIL that works in IT. It's nice to have something a bit heavier duty.

I tried to get the probes of multimeter between the plug and the wall socket, but I could not get a good voltage measurement, but I have to pull out the plug by the diameter of the probes, so that may affect the measurement.  I'm not expert in this area.  I need to find my "Kill A Watt" meter. 
Title: Re: Another Melted 120V Charge Cable
Post by: Killroy on June 27, 2018, 03:59:55 AM
Is that a 12ga 5-15P to C13 power cord (similar to the one that comes with the bike) you are referring to?  If so, please let us know where we can source such a cord.  The heaviest I've seen these cords is 14ga.

I looked today and I have two 5-15P to C13 power cords, one from Amazon and one from San Jose BMW/Zero.  Both have identical markings and are 14 AWG.

The markings on the 5-15P is "YUNGLI YP-12" and "YUNG LI YC-12" on the C13.  These still may be different power cords, but they have the same components or copy. 
Title: Re: Another Melted 120V Charge Cable
Post by: jheth on June 27, 2018, 10:11:55 AM
The onboard charger seems to be the weak link in current design (mine failed on my 2015 SR too).
Simplest solution? Just get an external charger. If you don't need a $1000+ onboard quick charger (i.e. always charge overnight at home), try to find a deal on a Delta Q charger. I've been using one of these for a couple months, and it works great (just slow). It also draws less power from your wall outlet, which can be a good thing.


Sent from my iPhone using Tapatalk
Title: Re: Another Melted 120V Charge Cable
Post by: nedfunnell on June 30, 2018, 02:06:28 AM
Is that a 12ga 5-15P to C13 power cord (similar to the one that comes with the bike) you are referring to?  If so, please let us know where we can source such a cord.  The heaviest I've seen these cords is 14ga.

I looked at mine and it is indeed 14awg. My error- I think it has some extra insulation or something, since it's definitely the thickest C13 cable I've ever seen.
Title: Re: Another Melted 120V Charge Cable
Post by: togo on June 30, 2018, 05:41:47 AM
> > Step 1 is to check your voltage on the wall.[/quote]

> +1. If it's low it's a bit expensive to reliably increase at high power levels, but always good to know.

+1

Constant power means more amps when voltage is low.  Heat generated is power loss at a point of resistance, P=I^2R

Heat is based on the *square* of the current.  So low voltage means a lot more heat at the dirty contact when current increases.

Look for resistance points, clean those contacts.

And watch out for low voltage.

And don't forget there's a crimp behind the C13, if you feel heat coming from in there, you might have a bad crimp.