# Electric Utility Cart

#### Hightower1027

Joined Dec 23, 2021
2
I am trying to design a battery powered utility cart that runs on a track. I have found some motors that would work for the drive wheels, but they require 130VDC to operate. Is this doable with a batteries? There would be 5 of these motors each drawing about 3.3A (about 16.5A total). Seems I could put about 11 12V batteries in series but I have never worked with such high DC voltage before.

#### Alec_t

Joined Sep 17, 2013
12,819
Welcome to AAC!
What length of time do you intend to run the motors before the batteries need re-charging? That will determine the battery capacity required. The batteries will need a proper management system to ensure safe, balanced charging. The motor start-up and speed control system could be quite involved.
What is your budget for this?

#### Hightower1027

Joined Dec 23, 2021
2
Welcome to AAC!
What length of time do you intend to run the motors before the batteries need re-charging? That will determine the battery capacity required. The batteries will need a proper management system to ensure safe, balanced charging. The motor start-up and speed control system could be quite involved.
What is your budget for this?
Thanks for the response! The cart would need to operate for about 30 minutes a day. Say an hour to be safe. The budget would ideally be somewhere between \$10,000-15,000 for the entire electrical control system. Including motors, batteries, and all controls.

#### Alec_t

Joined Sep 17, 2013
12,819
So you'd be looking for deep-cycle batteries each with a theoretical minimum capacity of ~20Ah (but a practical capacity somewhat greater might be better for reducing battery stress). The battery management and motor control systems are beyond my pay grade, but someone else here may be able to help.

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#### BobTPH

Joined Jun 5, 2013
4,937
How dud you determine the power needed? 16.5A at 130V is almost 3HP.

Bob

#### prepka

Joined Oct 5, 2020
20
What type of motors are you going to use and have they been purchased already. The speed of a DC motor determines the voltage it should be run at so you may not need 130V if you don't need maximum speed that is also true for ac motors somewhat on Variable frequency drives. since you are using 5 motors I suggest using torque mode to make them share the load. Additionally, you can use less but larger amp-hour batteries and boost the voltage.
the batteries should be individually recharged separately with multiple charging circuits as a string at 7-10% of capacity to preserve life and keep balance or have a charge balancing circuits on the batteries to maintain the string, You mention running on a track. Is this for railway operation, and if so, there is a whole set of regulations that must be followed that you will need to evaluate before you start your design