ADF pressurized test booths

Our client needed to set up booths enabling them to carry out pressure tests of explosion-proof electrical enclosures (ADF), in series or in development, allowing them to ensure compliance with current standards and standardized testing procedures.

Montanier provided a positive response and designed a solution enabling INERIS to perform its tests in accordance with the standard and in a repeatable manner, with:

• 1 high and medium pressure technical skid.
• 1 equipped test booth.
• 1 test control screen with recording.

During this design process, Montanier studied the standards in force, and technically transcribed their strict application in the equipment.

Description of the equipment produced:

Installation of a water booster pump unit with an adjustable pressure of 2 to 60 bars and a maximum water flow rate of 8 m3/H.

The new HP group allows, from a touch screen control box, placed next to the entrance door of the test room, by means of two water booster pumps, to carry out the various tests.

A first centrifugal pump performs tests from 2 to 10 bars at a flow rate of 8m3/H, the second high-pressure pump performs tests from 10 to 60 bars at a maximum flow rate of 8m3/H as well.

A fault message stops the cycle if the pressure is not maintained for the programmed duration.

Operating mode:

After connecting the equipment to be tested in the test booth, the operator selects the test mode on the touchscreen:

Pump I – pressure from 2 to 10 bar, or Pump II – pressure from 10 to 60 bar

He can then program the test pressure and its duration.

The test cycle proceeds with a slow start-up slope, followed by holding at the test pressure for the programmed duration, followed by decompression to shut it down.

A USB port on the front of the box allows editing of test parameters: date, time, requested pressure, pressure and duration obtained.

Operating principle:

Pressure regulation is ensured by an analog pressure sensor via RS232 communication with the PLC. The speed of the high-pressure pump's electric motor is controlled by an electronic frequency inverter (0 to 50 Hz).

An electrically modulating bypass valve (4/20 mA) ensures a proportional discharge into the buffer tank, depending on the pressure required and the leakage volumes necessary for the test.