Parachute valve: Regulation and testing of the parachute valve

How to regulate a parachute valve

In the GMV parachute valve (VC) manual there are two ways to regulate the VC, but in practice the most useful way is to regulate the VC according to the flow rate of the plant, depending on the type or size of the VC and the number of turns of the screw.

We will explain this last method as an example.

Table for regulating the parachute valve

We take as an example the one indicated in blue in the table above:

To regulate a 1”1/4 VC valve to 125 l/min. the following steps would be carried out:

1) Close the adjustment screw (located in the center of the face opposite the hose connection) completely, until it stops, without tightening it.

2) Open the adjusting screw 7 ¼ turns.

The VC would be calibrated for a flow rate of 125 l/min. After adjusting the VC, it is advisable to check the correct operation of the valve.

Testing the parachute valve

To test the VC, the most unfavorable case must be simulated, a hose break or an uncontrolled speed or free fall. To do this, the following steps must be followed:

1. Send the cabin to the top floor.
2. Put the group into VC test mode.
   1. Group 3010: Close screw #5 (located on the side of the VRFP valve) completely.
   2. NGV Group A3: Activate menu 9.2 on the programming console.
3. Send the cabin down one floor. In test mode, overspeed is achieved, which will activate the VC.

Note: The test must be carried out at full load as indicated by the current regulations EN 81.2 A3 Annex D section R and EN 81.20 section 6.3.8 which will come into force in August 2017.

For further information, you can consult the manual for the parachute valve included in all the VC's supplied by GMV or on our website: http://www.gmveurolift.es