Winegrowers Supplies
- power inverters - some advice
If you wish to use machinery which has a 3-phase (380/400 volt) motor, but you do not have a 3-phase electricity supply there are two options:-
1. Buy a 3-phase inverter.
There are many types and sizes, for example, for smaller
machines:-
http://www.machinemart.co.uk/shop/product/details/pc-40-3-5hp-phase-converter/path/transformers-inverters-phase-converters-sol
The Clarke PC-40 is a compact power converter - designed
to enable 400v, 3-phase motors & equipment to operate when only 230v
mains power is available; it converts 230v 1-phase input into 380-415v 3-phase
output. The PC-40 has adjustable power output to match the requirements of motors up to a max. of 3.5
hp (4.75 kWatt); www.sitebox.ltd.uk sell at £224.10 + Vat.
The PC-40 works successfully to power a Voran 100P2 pack press with AMH mill
running, although it must be wired through a 20 Amp MCB to allow for short peak
loads; it should not be connected to a 13 amp socket.
There is also a PC-60 model which is for motors up to 5.5 hp (7.4 kWatt); www.sitebox.ltd.uk sell at £269.10 + Vat. This must be wired through a 32 Amp MCB.
Advice is to choose an inverter with at least 2x the power of the motor, and 3x for some types of motor.
Note: 1 kWatt = 0.746 horsepower (electric) = 0.7354988 horsepower (hp)(metric,DIN,PS) = 0.7457 horsepower (hp)(UK).
For larger motors I suggest talking to an expert, David on 01623 720 730.
http://stores.ebay.co.uk/Drives-Direct-Inverters-LTD?_trksid=p4340.l2563
- First read 'How to Choose'.
He sells an MA7 (up to 7Hp / 9.4 kWatt) @ £750 + £12 delivery + vat, which needs to be wired up to a 40 amp single phase supply (through a separate MCB, like an oven is). The MA7 has soft start and lots of other advantages, which you can read about on his website.
Or if your motor is dual-voltage then you could have it re-wired as 230v 3-phase, and use an inverter from 230v 1-phase input to 230v 3-phase output, which is much smaller and cheaper than a 380v inverter.
or
2. Replace the 3-phase motor with a single-phase one.
For example for a Voran 100P2 pack press:-
A new single-phase motor and switch cost about £100 + Vat
(e.g. from Amtecs in Hungerford www.amtecs.co.uk)
and works without starters etc (it does have a couple of large capacitors).
Note: all electrical work needs to be carried out by a qualified electrician.