2250kW 3.3kV Air-Cooled and Water-Cooled Drive

Usually the manufacturers know their products best, but you can certainly ignore their advice at your own risk and peril. Just remember that when the unit fails you will receive no warranty coverage. The choice is yours.

Thank you, But we have done a similar 2250kW 690V VFD same application with a air cooled drives and it is working good, is it because we are using high voltage VFD for the same power we need to use water cooled drives?

Going for a 3.3kV motor and Drive will it bring down by running cost of the equipment? since the current drawn for the same 2250 kW is less. if so, why Drive manufacturers are not recommending 6.6kV motor and VFD?

"... why Drive manufacturers are not recommending 6.6kV motor and VFD?"

Call them and ask. What could be easier?

It's time. Do let the forum know the outcome of the calls to the drive manufacturer, as there is always something to share and be learned from it.

So what if the current is less? The voltage is more. You are billed by wattage, not by amperage.

OK. Warranty seems to be going out the window.

Perhaps 690V without water cooling is more expensive than 3.3kV with? In any case, you would normally tell the vendor what supply voltage is available, not vice-versa.

Absolutely. It's not going to be solved by email or by technical blogging. GA.

Dear Member,

The cooling effect achieved with in the permissible level is the criterion. Both air cooling design and water cooling design is unique and have its own merits and de-merits. The cost difference is mainly due to the the size of the cooling device.

Air cooling device - has low over-all heat transfer co-efficient, and water cooling device has higher over-all heat transfer co-efficient.and it may be in the order of 1;2.2 ratio.

Therefore the air cooling device will be larger in size and hence costly.

Better follow the manufacturer's instructions, to get the best out of the equipment.

DHAYANANDHAN.S

Edited Removed Bold - CR4 Admins

Quit shouting.

"Better follow the manufacturer's instructions, to get the best out of the equipment."

How's that 90 kW motor coming along?

I am in the midst of a project with 4 x 4,000HP (roughly 3,000kW) 4160V VFD driven motors, the end user is demanding air cooled VFDs. To facilitate this, they need 15,000CFM (cubic feet per minute) of air flow for each drive, which equates to roughly 425 CMM, with the air temperature being a maximum of 30 degrees C. I can imagine that for yours, that would be only slightly less air flow. On my project, the drives and motors are in a relatively clean area; a water treatment plant. In a mine environment, that much air is going to bring with it a LOT of contaminants (pollution). So either that VFD will have to suffer the rigors of being dirty all the time, or there will need to be some extreme filtering and if someone forgets to change the filter, you could lose the VFD in short order. Liquid cooling means using heat exchangers mounted somewhere else, so moves that high volume of air movement to a different location where the contaminants are less critical.

We understand from the manufacturer that water cooled drives are compact and the number of fuses and wires running into the panels will be less. Since this is Drive panels are compact it does not provide any advantage on reducing running cost or capital purchase cost. In fact the initial investment is high. Water cooled is preferred in industries where the chillers are available for their factory use. Air cooled system are relatively larger and prices are better than water cooled.

This forum doesn't usually get involved with money.

Not necessary.You can have aircooled motors too .water cooled motors have their own problems and additional requirements of piping relays to monitor water flow etc but aircooled apart from normal protection nothing else is required .air cooled motor may be in one higher frame compared to water cooled but over all cost including piping , accessories will more or less even out .