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70 Posts
Discussion Starter #1
All,

I seem to be having rather poor luck in my attempt to convert my
truck and I think I may have a major problem.

I have my motor (ADC 9 inch) hanging from a crossbrace that attaches
to the original engine mounts. I also rigged up a battery rack
holding 3 batteries that sits on top of this cross brace. The other
day I noticed that there is only a 3/16 inch gap between the battery
rack (3/8 inch angle iron) and the A2 post of the motor.

Even with my lack of knowledge about things electrical, it seems that
the battery rack touching the motor terminal would not be a good
thing (either electrically or physical damage to the motor terminal).

My attempts to push the battery rack closer to the motor terminal are
not successful but I suspect the forces of breaking may be great
enough to cause the battery rack to touch or come closer to the motor
terminal.

Am I correct that it is bad/dangerous for the battery rack to contact
the motor terminal?

If they don't touch how close is too close?

My system is 144v flooded pack with a zilla 1k controller.

Thanks in advance.

John in Western Ma

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Registered
Joined
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70 Posts
Discussion Starter #2
> I have my motor (ADC 9 inch) hanging from a
> crossbrace that attaches
> to the original engine mounts. I also rigged up a
> battery rack
> holding 3 batteries that sits on top of this cross
> brace. The other
> day I noticed that there is only a 3/16 inch gap
> between the battery
> rack (3/8 inch angle iron) and the A2 post of the
> motor.
>
> Even with my lack of knowledge about things
> electrical, it seems that
> the battery rack touching the motor terminal would
> not be a good
> thing (either electrically or physical damage to the
> motor terminal).
>
> My attempts to push the battery rack closer to the
> motor terminal are
> not successful but I suspect the forces of breaking
> may be great
> enough to cause the battery rack to touch or come
> closer to the motor
> terminal.
>
> Am I correct that it is bad/dangerous for the
> battery rack to contact
> the motor terminal?
Yes. The vehicle chassis is effectively "ground", and
runs your aux. system, as it was in its gas burning
days. The high voltage pack is "floating". As you
drive, it is likely that your transmission will move.
Whether it goes 1/8, or 3/16" is yet to be determined.
Hard rubber will isolate, provided it is durable, and
inspected often, and that you can get it to stay on.
I don't see forces involved in braking as the issue.

As far as electricity arcing through the air, it can
happen, but there are other issues: is electrolyte all
over your battery tops? Where are the EMFs in your
electric motor? And probably a host of others that
I'm missing as a novice.
>
> If they don't touch how close is too close?
>
> My system is 144v flooded pack with a zilla 1k
> controller.
>
> Thanks in advance.
>
> John in Western Ma
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>


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Registered
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70 Posts
Discussion Starter #3
Hello John,

In our electrical work, which includes buildings and overhead line, a
voltage of 0 to 599 volts is consider to be low voltage, a voltage of 600 to
4999 volts is medium voltage and 5000 volts and above is call high voltage
and is label as such.

The low voltage of 144 voltage which may be charge may have a maximum
charge voltage of 186 volts may have enough clearance. The motor terminals
going through the motor may only have 1/8 inch clearance through the
bushings.

If you that close with a steel battery rack, I would cover all the exposed
motor and any other terminals with a insulation bolt covers or cap. They
look just like large vacuum caps. I use this type on all my exposed
terminal bolt connections.

I use a double cap on some of these terminals. One vinyl bolt cap that just
covers the bolt threads, and then another large vacuum soft rubber type that
covers this vinyl cap and goes over the nut.

I get the vinyl bolt caps from a hardware store and the vacuum caps from a
auto parts store.

If you have venting type of batteries, even some of the seal batteries have
vent ports on them, the venting of electrolyte could make the surface of the
battery conductive, the battery rack conductive and any surrounding material
conductive.

I have found even if my 180 volt battery pack is 10 feet away from the
motor, and when charging, it cause a conductive path across the battery
surfaces, across the surface of a epoxy coated fiberglass battery box and to
the frame of the vehicle.

The motor is attach to the cross member which was even on rubber motor and
transmission mounts, but the driveline connecting to the rear axle completed
a conductive path to the frame. So when the batteries are being charge, this
complete on loop of the charging circuit from the battery to the motor case.

As the motor brush dust builds up in the motor, then this current will
conduct from the motor shaft up the face of the commentator. This is what
to me, and while I was charging, I could see slight arcing from the surface
of the batteries and from the motor shaft to the commentator with the lights
off.

When the motor is new, check the resistance of the motor terminals, not
connected to the controller, to the motor frame and record this for future
reference. It may read over 20 meg ohms at first. As time goes on, this
resistance may reduce down to 50 K ohms or lower. Then its time to clean
the motor with a electric motor cleaner, you can also get at a auto parts
store or a motor shop.

To solve this, I use two more contactors to isolated the batteries from the
main contactor and motor controller. I also use another smaller 50 amp
contactor on the DC output of the battery charger to the batteries, so the
battery charger can be disconnected from the batteries during the time they
are being use or during maintenance.

I found if I disconnect any one of the links of the batteries with the
battery charger connected, even if was plug in, or connected directly to the
controller, they would arc, which makes it dangerous if there is hydrogen
present.

Roland


----- Original Message -----
From: "John" <[email protected]>
To: "Electric Discussion List Vehicle" <[email protected]>
Sent: Sunday, August 26, 2007 9:24 AM
Subject: [EVDL] High voltage leakage/shorting question


> All,
>
> I seem to be having rather poor luck in my attempt to convert my
> truck and I think I may have a major problem.
>
> I have my motor (ADC 9 inch) hanging from a crossbrace that attaches
> to the original engine mounts. I also rigged up a battery rack
> holding 3 batteries that sits on top of this cross brace. The other
> day I noticed that there is only a 3/16 inch gap between the battery
> rack (3/8 inch angle iron) and the A2 post of the motor.
>
> Even with my lack of knowledge about things electrical, it seems that
> the battery rack touching the motor terminal would not be a good
> thing (either electrically or physical damage to the motor terminal).
>
> My attempts to push the battery rack closer to the motor terminal are
> not successful but I suspect the forces of breaking may be great
> enough to cause the battery rack to touch or come closer to the motor
> terminal.
>
> Am I correct that it is bad/dangerous for the battery rack to contact
> the motor terminal?
>
> If they don't touch how close is too close?
>
> My system is 144v flooded pack with a zilla 1k controller.
>
> Thanks in advance.
>
> John in Western Ma
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 

·
Registered
Joined
·
70 Posts
Discussion Starter #6
Thanks all for the responses,

My batteries are in a plywood box that sits in the angle iron
bracket. I suppose venting spray will eventually make it to the
rack, but hopefully the box will slow that process down.

My concern is that when I had the batteries in the box before I
connecting the motor, the rack moved QUITE a bit. Connecting the
motor stabilized the system, but my fear is that when I break, the
battery box
will want to keep moving forward, and rotate the rack more than then
when I try to move the box by had.

I think for phase 1 I will look for the terminal caps that roland
mentioned or gluing a piece of non-conductive material to the bottom
of the rack.

Does anyone else see a problem with having batteries connected to the
motor mount. I figured putting the batteries on the motor mount would
be good because it puts the
battery and motor weight in the exact place the original designers
wanted it.

Thanks again,

John

Roland Wiench wrote:

> Hello John,
>
> In our electrical work, which includes buildings and overhead line, a
> voltage of 0 to 599 volts is consider to be low voltage, a voltage
> of 600 to
> 4999 volts is medium voltage and 5000 volts and above is call high
> voltage
> and is label as such.
>
> The low voltage of 144 voltage which may be charge may have a maximum
> charge voltage of 186 volts may have enough clearance. The motor
> terminals
> going through the motor may only have 1/8 inch clearance through the
> bushings.
>
> If you that close with a steel battery rack, I would cover all the
> exposed
> motor and any other terminals with a insulation bolt covers or cap.
> They
> look just like large vacuum caps. I use this type on all my exposed
> terminal bolt connections.
>
> I use a double cap on some of these terminals. One vinyl bolt cap
> that just
> covers the bolt threads, and then another large vacuum soft rubber
> type that
> covers this vinyl cap and goes over the nut.
>
> I get the vinyl bolt caps from a hardware store and the vacuum caps
> from a
> auto parts store.
>
> If you have venting type of batteries, even some of the seal
> batteries have
> vent ports on them, the venting of electrolyte could make the
> surface of the
> battery conductive, the battery rack conductive and any surrounding
> material
> conductive.
>
> I have found even if my 180 volt battery pack is 10 feet away from the
> motor, and when charging, it cause a conductive path across the
> battery
> surfaces, across the surface of a epoxy coated fiberglass battery
> box and to
> the frame of the vehicle.
>
> The motor is attach to the cross member which was even on rubber
> motor and
> transmission mounts, but the driveline connecting to the rear axle
> completed
> a conductive path to the frame. So when the batteries are being
> charge, this
> complete on loop of the charging circuit from the battery to the
> motor case.
>
> As the motor brush dust builds up in the motor, then this current will
> conduct from the motor shaft up the face of the commentator. This
> is what
> to me, and while I was charging, I could see slight arcing from the
> surface
> of the batteries and from the motor shaft to the commentator with
> the lights
> off.
>
> When the motor is new, check the resistance of the motor terminals,
> not
> connected to the controller, to the motor frame and record this for
> future
> reference. It may read over 20 meg ohms at first. As time goes
> on, this
> resistance may reduce down to 50 K ohms or lower. Then its time to
> clean
> the motor with a electric motor cleaner, you can also get at a auto
> parts
> store or a motor shop.
>
> To solve this, I use two more contactors to isolated the batteries
> from the
> main contactor and motor controller. I also use another smaller 50
> amp
> contactor on the DC output of the battery charger to the batteries,
> so the
> battery charger can be disconnected from the batteries during the
> time they
> are being use or during maintenance.
>
> I found if I disconnect any one of the links of the batteries with the
> battery charger connected, even if was plug in, or connected
> directly to the
> controller, they would arc, which makes it dangerous if there is
> hydrogen
> present.
>
> Roland
>
>
> ----- Original Message -----
> From: "John" <[email protected]>
> To: "Electric Discussion List Vehicle" <[email protected]>
> Sent: Sunday, August 26, 2007 9:24 AM
> Subject: [EVDL] High voltage leakage/shorting question
>
>
>> All,
>>
>> I seem to be having rather poor luck in my attempt to convert my
>> truck and I think I may have a major problem.
>>
>> I have my motor (ADC 9 inch) hanging from a crossbrace that attaches
>> to the original engine mounts. I also rigged up a battery rack
>> holding 3 batteries that sits on top of this cross brace. The other
>> day I noticed that there is only a 3/16 inch gap between the battery
>> rack (3/8 inch angle iron) and the A2 post of the motor.
>>
>> Even with my lack of knowledge about things electrical, it seems that
>> the battery rack touching the motor terminal would not be a good
>> thing (either electrically or physical damage to the motor terminal).
>>
>> My attempts to push the battery rack closer to the motor terminal are
>> not successful but I suspect the forces of breaking may be great
>> enough to cause the battery rack to touch or come closer to the motor
>> terminal.
>>
>> Am I correct that it is bad/dangerous for the battery rack to contact
>> the motor terminal?
>>
>> If they don't touch how close is too close?
>>
>> My system is 144v flooded pack with a zilla 1k controller.
>>
>> Thanks in advance.
>>
>> John in Western Ma
>>
>> _______________________________________________
>> For subscription options, see
>> http://lists.sjsu.edu/mailman/listinfo/ev
>>
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 
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