Liftgate batteries are charged when the truck is connected to the trailer. Since the batteries are usually close to the back of a trailer, long cables are needed to charge them. When current has to travel a long distance, it is going to lose some of its strength along the way; this is called voltage drop. Excessive voltage drop leads to batteries continuously operating at a low state of charge. This leads to unreliable batteries, road calls and shorter battery life.

Purkeys’ Chief Creative Engineer Bruce Purkey serves as chairman of the Liftgate Voltage Drop Test Procedure. This is a TMC task force working to develop a recommended practice for measuring voltage drop in liftgate charging circuits. This will standardize how fleets can test liftgate voltage drop and know if it is excessive or not. Having this information will help fleets identify charging issues before they cause road calls or delays.

According to Bruce, coming up with a recommended practice for liftgate voltage drop isn’t about how fleets should test. Instead, the main issue for the task force is determining which numbers should be used as the standard measurement. Since these numbers have never been published before, a lot of data has to be collected before moving forward.

Purkeys and other industry experts are working together to collect data from fleets across the U.S. The data collected shows the task force real world applications, different variations and where the issues are.

The TMC Task Force’s recommended practice will help fleets know if too much energy is lost due to voltage drop. This recommended practice will help fleets troubleshoot issues before they result in road calls.