Endurance Test: 24-Volt Reciprocating Saw
The 24-volt saw gave consistently good performance under all tests conducted. The "no load" test time, where the saw was allowed to run without cutting anything until the motor action stopped, averaged between 17 and 18 minutes.
A series of 24-volt battery endurance times measured during aggressive, constant cutting tests of vehicle A-pillars ranged from five minutes, 18 seconds to six minutes, 39 seconds. During one test, I cut the A-pillar seven times, sliced through the B-pillar 12 times, and still had enough power to cut the steering wheel ring three times. During a test where the battery ran for six minutes, 28 seconds, I cut completely through the driver’s side rocker channel 20 times.
6:28 (rocker, 20 cuts)
6:39 (one column, two door hinges, seven C-pillars)
5:18 (seven A-pillars, 12 B-pillars, three steering wheel ring cuts)
Immediately after use, the batteries are warm to the touch. They require a cool-down period before the charger unit will begin to recharge them. Recharge time is about one hour.
In the fire service, we routinely attack structure fires with on-board water in the apparatus booster tank. This initial fast attack is then supported by a sustained water supply from a hydrant line or tanker operation. DeWalt has taken this age-old fire service tradition and adapted it to the field of cordless saw technology with the introduction of a 24-volt AC/DC converter accessory. The AC/DC converter concept will revolutionize the application of cordless tool technology for the fire service.
To use this amazing converter, the saw operator simply removes the 24-volt battery and slides the AC/DC converter into the handle. With its electric power cord plugged into a 110-volt power source, the 24-volt saw runs indefinitely.
This accessory makes any complaints or concerns about battery endurance moot. Start with the cordless off a single 24-volt battery. With the “initial attack” cutting underway, a partner has more than five minutes to start a generator, plug in an electrical cord, and advance the line with the AC/DC converter to the saw operator. The operator stops long enough to remove the cordless battery and slide in the converter. In seconds, the cordless saw now has unlimited run time.
If you do not yet have a reciprocating saw in your fire and rescue tool inventory, then this is the saw kit to buy. If you have an 18-volt system, make it your backup up and upgrade to the state-of-the-art 24-volt technology with the AC/DC converter. It’s the best of both worlds.
Ron Moore, a Firehouse contributing editor, is a battalion chief and the training officer for the McKinney, TX, Fire Department. He also authors a monthly online article in the Firehouse.com “MembersZone” and serves as the Forum Moderator for the extrication section of the Firehouse.com website. Moore can be contacted directly at Rmoore@firehouse.com.