NR NR/L2/SIG/11774/SR0001TA ISSUE 1 PDF

Introduction

This Part is a brief description of the procedure to be adopted when attending a Clamplock failure. It does not include drive circuits or line circuits, which are common to most power operated points. It is presumed that the point drive circuits and the hydraulic power pack are functioning correctly. To check the power pack, observe the hydraulic hoses for flexing and relaxing during attempted power operation. A single ended set of points will be considered. (For double ended points, check both ends.) The following is by no means a complete list of all failures. It is designed to aid true fault location in order to prevent other adjustments or actions being used to overcome the failure.

Testing

Always obtain the signallers permission before any tests are carried out.

Note:

The disconnection's shown in NR?SMS/PB11 are for single ended sets. If facing point lock or detection tests are to be carried out on multiple ends ALL ends shall be isolated at the applicable pump units before work commences. Correct correspondence of ALL ends SHALL be maintained throughout the tests. This allows all testing to be carried out with reference to the voltage of the circuit under test and prevents the unintentional movement of any other ends.

Manually prove any adjustments are correct by hand pump operation before restoring to power operation by turning the switch on the Hydraulic Power Unit to the 'POWER' position. Finally test by operation from the signal box and observe that the apparatus functions correctly.