Additional information on how to descend with PMX and ACX.

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While investigating a few quality claims, we have realized that some clarifying additional information is needed reagarding how to descend with PMX and ACX ascenders to avoid these issues and prolong the product lifetime.

Descending with PMX

For shorter descents such as for work positioning shorter than 2 meters the descent lever alone may be used. For longer descents always position the rope around the friction brake, tighten, then open the descent lever fully and regulate the speed with the rope friction instead of the lever. Recommended descending speed should be the same as ascending speed; Approx. 17 meters per minute. The user manual states 0,5 m/s or 30 meters per minute as maximum descent speed, but for maximum product lifetime, use the recommended speed above.

Using only the descent lever to regulate the speed on longer descents puts unnecessary wear on the clutch and will lead to higher maintenance and repair costs.

Descending with ACX

When starting your workday with a traditional ground up ascent the feature of regenerating energy while descending to charge the battery gives the user some extra battery range. However, if starting top down this feature becomes a limitation as there is nowhere for the energy to go if the battery is already fully charged. Therefore, the descent speed will be very slow if this is attempted, and we strongly recommend that this work procedure is avoided. Some users have then used the emergency descent to increase the descent speed and work around the limitation, in some cases leading to damaged machines and batteries. Here are some clarifications and advice for how to handle avoid this.

• Plan your work so that starting descents on a full battery is avoided.

• Any distance that has been ascended can always safely be descended on the same battery.

• Only use Emergency descent as an emergency measure, using emergency descent wears the brake disc and will lead to higher maintenance costs.

• The emergency descent speed is user regulated but should be kept to slower than 24 meters per minute speed. Using Emergency descent bypasses many of the electronic safety systems and you risk damaging the ACX or battery if higher descent speeds are used, such damage will not be covered by warranty.

• Emergency descent shall not be practiced over long distances for training purposes, one or two meters at low speed is enough to understand how it works.

• If possible, use a Portable Power Supply (PPS) which will allow for top down work almost without limitations.

• The battery doesn’t have to be fully charged if you know that the next day will start with top down work, the charging process can be aborted at any given point at a charging level suitable for next job.

The ACX can also be run full speed with remote control without load for 5-15 minutes to discharge the battery enough to safely and efficiently operate on top down jobs. Approximate time from 100% charge:

• 5 minutes to reach 90% charge where battery charge level will no longer limit the operation. After this point each minute will add 15 meters of decent capability with 100kg.

• 10 minutes will give 5 x 15 meters = 75 meters descent capability with 100kg.

• 15 minutes will give 10 x 15 meters = 150 meters descent capability with 100kg.


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