UV dryers... mercury vapor or other high pressure gas discharge lamps of some sort for UV generation? If unballasted, should just result in lower output. That may then in turn mean longer drying time per cycle, which means the lampos are on for longer and may end up having shorter production life.
If ballasted, such as with metal halide for instance, the lower voltage may also have adverse effects on a switch-mode ballast.
Just get a buck-boost transformer and step it back up to 220V. Shouldn't cost much at all and probably a LOT less than whatever negative effect you might have; either way.
In North America 240:12 and 240:24 transformers are readily available.
In an autotransformer configuration, a 240:12 will boost 208 volts to 218.4 volts.
A 240:24 will boost 208 volts to 228.8 volts.
Either voltage should be suitable for 220 volt rated equipment.
The secondary winding (12 V or 24 V) must be rated for the full load current. This will result in a transformer KVA rating much less than the load KVA. That's one of the advantages of an autotransformer connection.
Bill
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"Why not the best?"
Jimmy Carter
