EPU Questions

Topic 30569 | Page 1

Page 1 of 2 Next Page Go To Page:
Mikey B.'s Comment
member avatar

I just got a new truck which has an EPU. My last truck had an APU. The APU kept the truck cool even in this heat (not perfectly cool but cool nonetheless) it seems like the EPU doesn't do as good a job of cooling. Am I imagining this or do you have firsthand knowledge of this being a fact? I know the EPU runs off a separate battery pack on frame behind the cab, does this run till it shuts everything non essential down then die or does it start the truck to keep its batteries charged?

APU:

Auxiliary Power Unit

On tractor trailers, and APU is a small diesel engine that powers a heat and air conditioning unit while charging the truck's main batteries at the same time. This allows the driver to remain comfortable in the cab and have access to electric power without running the main truck engine.

Having an APU helps save money in fuel costs and saves wear and tear on the main engine, though they tend to be expensive to install and maintain. Therefore only a very small percentage of the trucks on the road today come equipped with an APU.

EPU:

Electric Auxiliary Power Units

Electric APUs have started gaining acceptance. These electric APUs use battery packs instead of the diesel engine on traditional APUs as a source of power. The APU's battery pack is charged when the truck is in motion. When the truck is idle, the stored energy in the battery pack is then used to power an air conditioner, heater, and other devices

PJ's Comment
member avatar

There is a process you go through to set the truck to auto start when the voltage drops to a certain point. Once it charges up it will shut off. I think freighliner calls it opti idle. Each manufacturer is a bit different in their process to set it when you park.

Mikey B.'s Comment
member avatar

There is a process you go through to set the truck to auto start when the voltage drops to a certain point. Once it charges up it will shut off. I think freighliner calls it opti idle. Each manufacturer is a bit different in their process to set it when you park.

Yep, noticed the option idle setup piece on the panel while flipping through, haven't set it up yet. Will have to in the next couple days, thanks.

Also, I'm curious which items are powered by the EPU and which are powered by the trucks main batteries. Inverter, fridge, TV, lights etc. any ideas?

EPU:

Electric Auxiliary Power Units

Electric APUs have started gaining acceptance. These electric APUs use battery packs instead of the diesel engine on traditional APUs as a source of power. The APU's battery pack is charged when the truck is in motion. When the truck is idle, the stored energy in the battery pack is then used to power an air conditioner, heater, and other devices

PackRat's Comment
member avatar

What year is the truck? Manual or auto?

Mikey B.'s Comment
member avatar

What year is the truck? Manual or auto?

2022 freightliner cascadia, automatic.

PackRat's Comment
member avatar

On my truck there is a screen on the dashboard display for the Optimized Idle. My process is with the engine running, turn on the A/C in the sleeper and in the cab, go to the Vehicle Settings, then the Optimized Idle Screen. Click "Enable-OK" on the steering wheel button. Click OK on the next screen. Final screen prompt asking for Cabin Comfort-click okay to enable that.

The engine should run as long as the A/C fan is on in the sleeper, but if the truck registers the temperature inside as cooler than the outdoors temperature, it will normally stop the engine.

Rudy B.'s Comment
member avatar

What year is the truck? Manual or auto?

Any suggestions for a 2017 Peterbilt 579?

I'm debating a gas-powered generator on the catwalk with an Arduino controller as a backup to keep my batteries charged.

DUI:

Driving Under the Influence

Grumpy Old Man's Comment
member avatar

It depends.

I just found out there is an aftermarket copy of Freightliner’s system.

Guy asked me how it worked and he didn’t have an option for Interior Comfort. I went to look and his was an add on. The vents were on the back of the cab.

With mine when you enable Interior Comfort, it will start if the batteries are low OR if the AC can’t keep it cool enough using batteries.

I also have a factory inverter and Shore Power plug. When I go home I plug in, leave the key off and turn on the AC and it keeps the truck cool (or warm) and my fridge(s) doesn’t have to work so hard.

Grumpy Old Man's Comment
member avatar

0696852001628164897.jpg

Mikey B.'s Comment
member avatar

I meant to thank y'all for the help. I now use the Opti idle daily. I don't like leaving the key on but I can deal with it. I don't have the interior comfort setting so I start the truck, with front and rear A/C on I enable opti idle. The truck engine then shuts off with the EPU running until it drops to 12.2 volts then it starts up and runs for two hours then shuts off again. I haven't really paid attention to the idle when it starts up but I raise the idle to 900 rpm prior to turning it on. Hopefully it idles at 900 for the two hours but I'm usually asleep when it kicks on. Since I don't have the interior comfort mode I just adjust the front and rear settings to where it won't freeze me out when it starts. I like it cold though so I doubt it could do that.

EPU:

Electric Auxiliary Power Units

Electric APUs have started gaining acceptance. These electric APUs use battery packs instead of the diesel engine on traditional APUs as a source of power. The APU's battery pack is charged when the truck is in motion. When the truck is idle, the stored energy in the battery pack is then used to power an air conditioner, heater, and other devices

Page 1 of 2 Next Page Go To Page:

New Reply:

New! Check out our help videos for a better understanding of our forum features

Bold
Italic
Underline
Quote
Photo
Link
Smiley
Links On TruckingTruth


example: TruckingTruth Homepage



example: https://www.truckingtruth.com
Submit
Cancel
Upload New Photo
Please enter a caption of one sentence or less:

Click on any of the buttons below to insert a link to that section of TruckingTruth:

Getting Started In Trucking High Road Training Program Company-Sponsored Training Programs Apply For Company-Sponsored Training Truck Driver's Career Guide Choosing A School Choosing A Company Truck Driving Schools Truck Driving Jobs Apply For Truck Driving Jobs DOT Physical Drug Testing Items To Pack Pre-Hire Letters CDL Practice Tests Trucking Company Reviews Brett's Book Leasing A Truck Pre-Trip Inspection Learn The Logbook Rules Sleep Apnea
Done
Done

0 characters so far - 5,500 maximum allowed.
Submit Preview

Preview:

Submit
Cancel

Join Us!

We have an awesome set of tools that will help you understand the trucking industry and prepare for a great start to your trucking career. Not only that, but everything we offer here at TruckingTruth is 100% free - no strings attached! Sign up now and get instant access to our member's section:
High Road Training Program Logo
  • The High Road Training Program
  • The High Road Article Series
  • The Friendliest Trucker's Forum Ever!
  • Email Updates When New Articles Are Posted

Apply For Paid CDL Training Through TruckingTruth

Did you know you can fill out one quick form here on TruckingTruth and apply to several companies at once for paid CDL training? Seriously! The application only takes one minute. You will speak with recruiters today. There is no obligation whatsoever. Learn more and apply here:

Apply For Paid CDL Training

About Us

TruckingTruth was founded by Brett Aquila (that's me!), a 15 year truck driving veteran, in January 2007. After 15 years on the road I wanted to help people understand the trucking industry and everything that came with the career and lifestyle of an over the road trucker. We'll help you make the right choices and prepare for a great start to your trucking career.

Read More

Becoming A Truck Driver

Becoming A Truck Driver is a dream we've all pondered at some point in our lives. We've all wondered if the adventure and challenges of life on the open road would suit us better than the ordinary day to day lives we've always known. At TruckingTruth we'll help you decide if trucking is right for you and help you get your career off to a great start.

Learn More