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Getting Started

4 Getting Started with an Inverter

4.1Mounting the Inverter

Mount the inverter using the mounting holes provided as described in the Operating Instructions. Ensure the correct torque ratings for the fixing bolts are not exceeded.

The unit may be mounted horizontally or vertically without derating. Do not mount the units upside down or sideways, as the fan cooling will oppose natural convection cooling.

4.2Cooling

Many inverters will operate in a temperature of 50° C without de-rating.

Make sure that the inlet and outlet ducts are not blocked, for example by cables.

It is very important to ensure that the maximum operating temperatures are not exceeded inside a cubicle. When installing an inverter in a cabinet, it is necessary to calculate the heat rise:

1.Calculate total heat loss (Ploss) for all units inside the cabinet . Use manufacturers’ data or assume 3% loss.

2.For a sealed cabinet, calculate temperature rise using the formula:

Trise = Ploss/(5.5 x A)

Where A is the total exposed area of the cabinet in square metres.

For a fan cooled cabinet, calculate temperature rise using the formula:

Trise = (0.053 x Ploss)/F

Where F is the air flow in cubic metres /minute.

3.Add the Temperature rise to the external ambient temperature. If this is greater than the operating temperature of the drive, additional cooling will be needed, or the units must be de-rated.

It will also be necessary to de-rate at altitudes above 1000 m. Typical de-rating is as follows:

2000 m 85% of full load rating.

3000 m 75% of full load rating.

4000 m 65% of full load rating.

For more information consult the inverter supplier.

4.3Wiring up the Inverter

Warning

This Equipment must be Earthed

Note the warning guidelines in the Operating Instructions, and ensure all safety regulations are complied with.

Follow the wiring instructions in the Operating Instructions, including the EMC guidelines.

MICROMASTER Applications Handbook

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