Just seen a video on you tube where a company is offering a 30 ft boat using 2 48v batteries and is AC driving it. I am wondering what the range on that puppy is going to be.
Hi Forkingabout,
I am in need of a 72 volt series wound DC motor. Cheap as possible as I am on a budget. It would have to be 12KW and 12hP if possibe.
Any help would be appreciated? Sorry if this is in the wrong thread.
Regards
If you are in the business of running a warehouse or own a rental fleet and are directly comparing new AC vs DC, then AC would be the choice. As others have said, less parts, less maintenance, etc.
With a fleet of trucks my experience is the TCO will be lower on AC. With 1-2-3 pieces the cost savings will be minimal, especially if an AC controller needs replaced.
Choice of equipment manufacturer will have a big impact on whether there is any benefit to an AC powered forklift. I have many Crown Reach Trucks/ SP's I service and the costs are all low. My rental fleet is mostly Raymond Reaches/ OPC's, the costs with the AC is much lower. The new AC units are much better than a DC Easi that was expensive to run.
Do not do much work in high cycle environments like grocery so I have not seen the benefit of faster speeds. My current belief is that the productivity is close enough to be considered equal.
If you are moving from an older Raymond Easi to a new AC
No, thats one of the advantages of AC.
In the last 6 years I've replaced just 1 AC convertor due to a fault & another AC convertor due to the apprentice blowing it up changing the traction fuse ( he shorted the unit out by dropping his spanner across all the terminals )
I've not had to replace a single AC motor, only things ive done is bearing replacement including the odd speed sensor bearing.
Are there no brushes in an ac motor?
I personally prefer the dc systems. DC = brushes, contactors,contactor tips, component testing and replacing, hence more work to sell during a pm. AC controllers are much more complicated internally but as a forklift tech most of us will just replace inverters, encoders, and switches after a few simple test and/or an error code.
Half of the 30 Raymond orderpickers running around my warehouse are early 06s with AC drive. I haven't lost a motor yet (I'm knocking on my wooden desk as I type this) so worrying about having to rebuild one is a mute pointi think.
I was under the impression, ac motors are not cost effective to rebuild. I'm thinking this ac stuff is all smoke and mirrors
The Only downside can be I suppose the cost of AC motor controllers when they fail compared to most DC controllers.
The controllers themselves are harder to repair and more expensive to replace than many traditional DC controllers.
Ac systems are much easier to troubleshoot than the older dc systems. Inverters when bad most times are easy to detect. Much less operating parts. External sensors will be a welcome change however.
Only things ive ever had to replace on AC motors over the years are the bearings & the odd speed sensor bearing.
Newer stuff with AC wont have a speed sensor bearing, it will have a toothed wheel inside the motor & an external sensor - like an ABS setup on a car.
The advantages of AC power on the DC motor are: low maintenance AC motor by not using brushes, lower power consumption lets you use batteries with less capacity to amps hours. Are easier to repair when using copper wire in the coils which is cheaper than copper hearth using DC motors.