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Explosion proof inverter 1

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JJken

Electrical
Jun 17, 2009
5
Currently I have DC Explosion proof motor 100 W for air fan . The problem is brush wearing that cause motor stuck every two months.

I plan to install the flame proof inverter to convert DC 24V to 220 AC 1 ph to drive new AC motor ( replace DC motor ).

Anyone can suggest the manufacturer for such explosion proof inverter ?

The inverter can not be installed in safe location as it will be located in hazardous due to no available space in safe area.



 
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If you have shop air available, you might consider an air motor. Try Gast


Might be a lot cheaper and easier then a 1/10 Hp EP motor.

Be interesting to read the response on a 100 W, DC to AC, EP converter.

Ed
 
The air motor sounds like a good idea to me but, if you must use an inverter, consider buying a plain inverter and placing it in an explosion-rated box. You will need to carefully size the box so the inverter doesn't overheat but, at these low wattages, the heat should not be too much to deal with economically.

Did I say economically? In XP? Shucks, nothing is economical in XP? But, I meant, comparatively so!
 
Yeah, Dick, just remarkable what that EP tag will do to a price tag. Ain't it?

Ed
 
The inverter will be the size of a six-pack of beer. Are you really saying there is no room to mount something that size in the safe area? I'd have another look in the safe area.


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If we learn from our mistakes I'm getting a great education!
 
Why do need an inverter ? Use a 230 V ac fan directly. Or are you saying all your supply is at only 24 V DC ?
 
typical N.E.England view on things..relate everything to beer
:)

JJken
What about a mechanical variable speed device like the Kopp variator + suitable motor? They start at ratings 0.18kW and have a speed range 11:1 and depending on the motor, are suitable for explosion proof environments. The speed range is constant power so maybe a little overkill and 'old technology' but they work.
 
Beer is life. The rest is details. [tongue]




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If we learn from our mistakes I'm getting a great education!
 
Thanks for all advices.
This inverter will be located at off-shore wellhead platform. Only 24 Vdc is available. No shop air available
All area are classified.
That is why we need XP inverter which is rarely used.

The heat dissipation from XP enclosure is also one concern.
 
This fan has to be started first by 24 Vdc battery to purge air in other enclosure to make it as safe area.

Then this equipment shall be XP to start at any conditions.

 
Actually the motor will be run at constant speed. The purpose of inverter is just used for convert DC to AC motor .

When the XP motor will be drived by inverter, it must be rated for that purposed due to harmonics and low cooling at lower speed.

Whether Inverter rating duty motor is still needed or not if motor driven by inverter run at constant rated speed and inverter is pure sine wave type. ??

Combined test to get ATEX certificate for both motor and inverter is neccessary or not ?
 
Have thought about brushless DC (BLDC) motors ? The power of 100 W is within that range.
 
2 months life on a set of brushes seems somewhat excessive. Are the brushes the correct grade? You may be using a really big hammer to crack a very small nut - have you spoken to the motor manufacturer regarding the abnormal brush wear problems? There may be a simple and minimal cost solution.


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If we learn from our mistakes I'm getting a great education!
 
It is more difficult to find out brushless DC motor explosion proof type.

The inverter solution is proposed from main supplier who sell whole package of problem equipment.

Direct contact to motor manufacturer may be better solution as ScottyUK's comment.
 
JJKen, I am looking to source a 24 V DC Explosion proof motor, can you tell me who the supplier/manufacture of your 24 V Dc motor is?
 
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