Using the EJECT friction saver with single rope (SRT/SRS)
The EJECT friction saver was designed for use on doubled rope (DdRT/MRS), but it has also been tested and certified with a specific setup for use on single rope (SRT/SRS).
- Carefully read the Instructions for Use used in this technical advice before consulting the advice itself. You must have already read and understood the information in the Instructions for Use to be able to understand this supplementary information.
- Mastering these techniques requires specific training. Work with a professional to confirm your ability to perform these techniques safely and independently before attempting them unsupervised.
- We provide examples of techniques related to your activity. There may be others that we do not describe here.
The setup certified for SRT is as follows, as specified in the Instructions for Use:
- make a figure-eight knot that is blocked against the pulley, with a carabiner (required) attached to the loop of the knot.
- knot positioned to the right of the pulley.
The double overhand knot has also been tested in this configuration. The results show that it should not be used: it deforms under load and passes through the device at low loads, attainable in use (5 to 10 kN depending on the ropes tested).
Only the setup with the knot on the right is certified, but the setup with the knot on the left has been tested and approved by Petzl’s internal testing.
The figure-eight knot and the butterfly knot were tested to more than 12 kN without failure. However, as knot behavior under load is not always repeatable, Petzl recommends always attaching a carabiner in the loop of the knot, as a backup.
The knot may be positioned to the left or to the right of the pulley, depending on your work setup, on the passage of deviations during work and on your position at the time of retrieval.
In all cases, the user went to the anchor point to set up the friction saver. EJECT cannot be set up remotely.
In the two examples below, the rope splice after the stopper knot can be connected to any system that enables retrieval (AIRLINE, another rope or even the access rope to reduce the number of ropes. Attention: if you connect a rope, its weight can cause the stopper knot to move when the system is not under tension).
Example with the knot on the right
- During retrieval, the friction saver does not pass through the deviations made while working.
- During setup, the rope must be removed from the friction saver to install it in the other direction.
- The ZIGZAG must be removed from the rope for the retrieval.
The retrieval ball is attached to the end of the rope behind the ZIGZAG, by a clove hitch if the end does not have a splice.
Example with the knot on the left
- No removal of the rope from the ZIGZAG during setup and retrieval.
- The deviations made during work help brake the fall of the EJECT during retrieval.
- During retrieval, the friction saver will follow the same path that was taken during work: there is a risk of jamming in the deviations.
- For retrieval, you must first lower the stopper knot to untie it, install the retrieval ball, then finally retrieve the friction saver.