It is now becoming more common where the vehicle engine on an ice cream van can no longer be running during events. We have now converted a few vans to allow the engine driven Mr Whippy machine to run using a motor and batteries.
These machines are very power hungry, and as they are used during hot weather, it is important to use the correct specification of inverter. We always run the systems at 24v, as the 48v inverters are not type tested for mobile use, so using 24v removes this grey area, as they hold all the required certification.
This conversion uses an 8KVA Victron Quattro, this allowed the continuous running of the Mr Whippy machine and a coffee machine. The 8KVA unit will supply a continuous output of 6400w at 25 degrees, but as the temperature rises, the output reduces, when the inverter is at 60 degrees the output is reduced to 3600w. These temperatures will happen in the summer, so it may seem like an over kill, but it is required for reliability. If you just want to run the MR Whippy machine, this can be achieved using a 5KVA unit
The components used for the DC system are also very important for reliability, it is very important to ensure that no connection is allowed to reach temperatures above 50 degrees, if a fuse or bolted connection gets too hot, it is possible for the connection to loosen causing arching, this can be very dangerous. All the components we use in this type of installation are highest quality available.
The batteries fitted in this conversion are Fog Star Drift 24v, these batteries hold a 10 year warranty. The 3 batteries connected in parallel gave a total of 21KWH of storage. I am not a fan of increasing voltage by connecting 12v batteries in series. I prefer the battery BMS to be aware or the final voltage as this will increase reliability and safety.
With this configuration it is possible to trade for at least 8 hours before the batteries require recharging. If you add solar, this can be increased further.
The system was controlled and monitored by a Victron GX system, allowing real time data and remote access.
The motor installed to drive the machine was connected to the original drive shaft, so it was still possible to run the engine drive if required. A 3 phase motor with an inverter drive was in installed to reduce the start up current.
It is possible to run a machine fitted with a BOK compressor, but we always recommend that this type of compressor is swopped out for a Seltec compressor. There are 2 main reasons for this, the first is the BOK compressor runs at a far lower RPM than the Seltec unit. In order to reduce the drive speed, additional belts and pulleys are required, this causes friction and will reduce your working time considerably. The 2nd reason is the BOK compressor is very loud, to the extent that you may be accused of still running your engine!
For more information, please get in touch.
