Front	Rear	Left Side	Right Side

Front: Open for Rigging	Rear: Open for Rigging

Technical Details

I acquired my Edelrid Ohm from Backcountry Gear in 2017.

My Edelrid Ohm is 55 mm. long, 116 mm. wide, 38 mm. high, and weighs 473 g.

The Ohm consists of fixed and swinging plates with upper and lower stainless steel blocks fastened to the fixed plate and a quickdraw with an aluminum carabiner and a steel rapide link. The fixed rear plate has a 15.1 mm. hole at the top for attaching the quickdraw rapide. The front plate pivots on a concealed axle on the bottom block. This plate has a hook at the top that engages the rapide, and a spring-loaded plastic safety. Both plates have plastic covers. The lower block has a narrow V-shaped rope groove. The upper block has a rounded rope groove on the outer portion and a straight nose on the inner. A third plastic piece is attached above this block.

The front cover is molded with the Ohm logo ("OHM" over an Ω}, "Ø 8.9-11.0 mm," and "EDELRID" filled in with black paint. The front plate is etched with a climber icon and a dashed arrow. The rear cover is molded with the Ohm logo, "EDELRID" filled in with black paint, and "CE0123." The rear plate is printed with the Ohm logo, the Edelrid "e" logo, a climber icon and a dashed arrow. and Edelrid. The inside is etched with a climber icon, "O-2017-05-2425," a factory icon, and a dashed arrow. The rapide link is stamped with "MAILLON RAPIDE FRANCE," "EN365:05/Q&12275," "CE0032," "↔35kN ↕10kN," a book-with-an-"i" icon, and "UIAA. The tag on the Quickdraw has "EDELRID" and the Edelrid "e" logo on one side and "CE0123," "EN566," "22kN," "2017," "Made in Germany," a book-wtih-an-"i," and "bluesign® product" on the other. The carabiner has "EDELRID" and a book-wtih-an-"i" on one side, "kN↔23kN↕8" followed by an open carabiner icon followed by "8" and "CE0333" on the other, and "05" and "17" stamped on the spine.

Comments

The Ohm is an assisted-braking resistor designed to increase rope friction when there is a large weight difference between belayer and lead climber. It is used when both the climber and belayer are below a top anchor. In the event of a fall, the OHM increases the amount of rope friction so that a lighter belayer can hold a heavier lead climber without difficulty. Edelrid recommends that the weight difference between the lead climber and the belayer (lead climber > belayer) be in the range of 10 - 40 kg, and that the minimum weight belayer is 40 kg.

The Ohm works well, but it is quite heavy. This is not the sort of device that I would want to haul up a big climb, but for "sport" climbing at the local crag, I can see how some teams would like it.