Inverter Behaviour Normal?

[Jimbo]

Archived from groups: comp.sys.laptops (More info?)

I have a 175 watt Vector inverter that I use to power my laptop when I
travel. I had left it plugged in to one of the DC outlets after a
recent trip. It was switched off. Then I noticed when I turned off the
ignition, the radio continued to play for several seconds and the dash
lights stayed on for several seconds, etc. When I unplugged the
inverter, everything returned to normal.

What component/feature in an inverter would cause such behaviour?

jimbo

 

[Guest]

Archived from groups: comp.sys.laptops (More info?)

"jimbo" <jimbo@noway.com> wrote in message
news:10iq5n1btl0105f@corp.supernews.com...
| I have a 175 watt Vector inverter that I use to power my laptop when I
| travel. I had left it plugged in to one of the DC outlets after a
| recent trip. It was switched off. Then I noticed when I turned off the
| ignition, the radio continued to play for several seconds and the dash
| lights stayed on for several seconds, etc. When I unplugged the
| inverter, everything returned to normal.
|
| What component/feature in an inverter would cause such behaviour?
|

Releasing energy from the capacitors of your inverter back through the
circuit in your vehicle. If this is the case, it is a very poorly designed
or faulty inverter.

 

[Guest]

Archived from groups: comp.sys.laptops (More info?)

Jason Cothran <reply@board.nomail> wrote:
>
> "jimbo" <jimbo@noway.com> wrote in message
> news:10iq5n1btl0105f@corp.supernews.com...
> | I have a 175 watt Vector inverter that I use to power my laptop when I
> | travel. I had left it plugged in to one of the DC outlets after a
> | recent trip. It was switched off. Then I noticed when I turned off the
> | ignition, the radio continued to play for several seconds and the dash
> | lights stayed on for several seconds, etc. When I unplugged the
> | inverter, everything returned to normal.
> |
> | What component/feature in an inverter would cause such behaviour?
> |
>
> Releasing energy from the capacitors of your inverter back through the
> circuit in your vehicle. If this is the case, it is a very poorly designed
> or faulty inverter.

Why?
While it may be unexpected, I can see no reason why it's poor design.
A diode on the input would prevent this, but knock 5-10% off efficiency.
A relay or power FET could be used to prevent this, with little loss, but
it's going to add to the cost.

 

[Guest]

Archived from groups: comp.sys.laptops (More info?)

"Ian Stirling" <root@mauve.demon.co.uk> wrote in message
news:412d2843$0$63406$ed2619ec@ptn-nntp-reader02.plus.net...
| Jason Cothran <reply@board.nomail> wrote:
| >
| > "jimbo" <jimbo@noway.com> wrote in message
| > news:10iq5n1btl0105f@corp.supernews.com...
| > | I have a 175 watt Vector inverter that I use to power my laptop when I
| > | travel. I had left it plugged in to one of the DC outlets after a
| > | recent trip. It was switched off. Then I noticed when I turned off the
| > | ignition, the radio continued to play for several seconds and the dash
| > | lights stayed on for several seconds, etc. When I unplugged the
| > | inverter, everything returned to normal.
| > |
| > | What component/feature in an inverter would cause such behaviour?
| > |
| >
| > Releasing energy from the capacitors of your inverter back through the
| > circuit in your vehicle. If this is the case, it is a very poorly
designed
| > or faulty inverter.
|
| Why?

Bad or nonexistant diode.


| While it may be unexpected, I can see no reason why it's poor design.
| A diode on the input would prevent this, but knock 5-10% off efficiency.
| A relay or power FET could be used to prevent this, with little loss, but
| it's going to add to the cost.

See you answered it yourself <wink>

 

[Jimbo]

Archived from groups: comp.sys.laptops (More info?)

Jason Cothran wrote:
> "jimbo" <jimbo@noway.com> wrote in message
> news:10iq5n1btl0105f@corp.supernews.com...
> | I have a 175 watt Vector inverter that I use to power my laptop when I
> | travel. I had left it plugged in to one of the DC outlets after a
> | recent trip. It was switched off. Then I noticed when I turned off the
> | ignition, the radio continued to play for several seconds and the dash
> | lights stayed on for several seconds, etc. When I unplugged the
> | inverter, everything returned to normal.
> |
> | What component/feature in an inverter would cause such behaviour?
> |
>
> Releasing energy from the capacitors of your inverter back through the
> circuit in your vehicle. If this is the case, it is a very poorly designed
> or faulty inverter.
>
>

OK, but does the release of energy back into my vehicle circuit cause
any problem? Any chance of over voltage or high current causing
component damage to any device in my vehicle?

jimbo

 

[Guest]

Archived from groups: comp.sys.laptops (More info?)

Jason Cothran <reply@board.nomail> wrote:
>
> "Ian Stirling" <root@mauve.demon.co.uk> wrote in message
> news:412d2843$0$63406$ed2619ec@ptn-nntp-reader02.plus.net...
> | Jason Cothran <reply@board.nomail> wrote:
> | >
> | > "jimbo" <jimbo@noway.com> wrote in message
> | > news:10iq5n1btl0105f@corp.supernews.com...
> | > | I have a 175 watt Vector inverter that I use to power my laptop when I
> | > | travel. I had left it plugged in to one of the DC outlets after a
> | > | recent trip. It was switched off. Then I noticed when I turned off the
> | > | ignition, the radio continued to play for several seconds and the dash
> | > | lights stayed on for several seconds, etc. When I unplugged the
> | > | inverter, everything returned to normal.
> | > |
> | > | What component/feature in an inverter would cause such behaviour?
> | > |
> | >
> | > Releasing energy from the capacitors of your inverter back through the
> | > circuit in your vehicle. If this is the case, it is a very poorly
> designed
> | > or faulty inverter.
> |
> | Why?
>
> Bad or nonexistant diode.

So you'd rather have an inverter that uses 5-10% more battery, and
doesn't do this?

 

[Guest]

Archived from groups: comp.sys.laptops (More info?)

No, actually, I'd rather have an inverter whose on/off switch turns the
inverter off at BOTH ends.


Ian Stirling wrote:

> Jason Cothran <reply@board.nomail> wrote:
>
>>"Ian Stirling" <root@mauve.demon.co.uk> wrote in message
>>news:412d2843$0$63406$ed2619ec@ptn-nntp-reader02.plus.net...
>>| Jason Cothran <reply@board.nomail> wrote:
>>| >
>>| > "jimbo" <jimbo@noway.com> wrote in message
>>| > news:10iq5n1btl0105f@corp.supernews.com...
>>| > | I have a 175 watt Vector inverter that I use to power my laptop when I
>>| > | travel. I had left it plugged in to one of the DC outlets after a
>>| > | recent trip. It was switched off. Then I noticed when I turned off the
>>| > | ignition, the radio continued to play for several seconds and the dash
>>| > | lights stayed on for several seconds, etc. When I unplugged the
>>| > | inverter, everything returned to normal.
>>| > |
>>| > | What component/feature in an inverter would cause such behaviour?
>>| > |
>>| >
>>| > Releasing energy from the capacitors of your inverter back through the
>>| > circuit in your vehicle. If this is the case, it is a very poorly
>>designed
>>| > or faulty inverter.
>>|
>>| Why?
>>
>>Bad or nonexistant diode.
>
>
> So you'd rather have an inverter that uses 5-10% more battery, and
> doesn't do this?

 

[Guest]

Archived from groups: comp.sys.laptops (More info?)

There are potential problems. For example, service techs disconnect the
battery to prevent damage to the car's electrical system when servicing
electrical components. It's not a good design if the inverter will feed
backwards into the car's electrical system.

And while the diode may not be the best solution to THIS problem, the
diode will prevent damage to the inverter if it's connected backwards to
the car battery.


jimbo wrote:

> Jason Cothran wrote:
>
>> "jimbo" <jimbo@noway.com> wrote in message
>> news:10iq5n1btl0105f@corp.supernews.com...
>> | I have a 175 watt Vector inverter that I use to power my laptop when I
>> | travel. I had left it plugged in to one of the DC outlets after a
>> | recent trip. It was switched off. Then I noticed when I turned off the
>> | ignition, the radio continued to play for several seconds and the dash
>> | lights stayed on for several seconds, etc. When I unplugged the
>> | inverter, everything returned to normal.
>> |
>> | What component/feature in an inverter would cause such behaviour?
>> |
>>
>> Releasing energy from the capacitors of your inverter back through the
>> circuit in your vehicle. If this is the case, it is a very poorly
>> designed
>> or faulty inverter.
>>
>>
>
> OK, but does the release of energy back into my vehicle circuit cause
> any problem? Any chance of over voltage or high current causing
> component damage to any device in my vehicle?
>
> jimbo

 

[Guest]

Archived from groups: comp.sys.laptops (More info?)

jimbo <jimbo62@spamex.com> wrote:
> Jason Cothran wrote:
>> "jimbo" <jimbo@noway.com> wrote in message
>> news:10iq5n1btl0105f@corp.supernews.com...
>> | I have a 175 watt Vector inverter that I use to power my laptop when I
>> | travel. I had left it plugged in to one of the DC outlets after a
>> | recent trip. It was switched off. Then I noticed when I turned off the
>> | ignition, the radio continued to play for several seconds and the dash
>> | lights stayed on for several seconds, etc. When I unplugged the
>> | inverter, everything returned to normal.
>> |
>> | What component/feature in an inverter would cause such behaviour?
>> |
>>
>> Releasing energy from the capacitors of your inverter back through the
>> circuit in your vehicle. If this is the case, it is a very poorly designed
>> or faulty inverter.

> OK, but does the release of energy back into my vehicle circuit cause
> any problem? Any chance of over voltage or high current causing
> component damage to any device in my vehicle?

Basically not.
Auto stuff has to be overbuilt.
The "normal" (car starts and runs for a few hours, or will continue to run)
range may vary from 9-16V.
Under various common fault conditions, it can spike to 40-80V.
The added capacitance will generally only do good things.

The reason why the switch is behind the capacitor is because a switch
to cope with the large current surge when the switch is turned on from
cold is rather expensive (comparatively).
But, the lighter socket is designed to carry and interrupt these sorts
of currents.