I have a job next week wiring a UV heater for a printing press. The heater is rated at 80 amps. I have never messed with these before. Do I need to upsize my breaker at all or does it get wired as it is rated? It is 240v 3ph. I don't do much 3ph work so this is a little out of my league.
UV heater is not quite right. It is actually UV bulbs for a drying process in their flexographic printing process. They currently have a 240VAC 3 phase service that we installed the 240VAC service about 7 years ago. I worked for my dad at the time so I'm not sure exactly why. Something with the POCO and available power in a rural residential area. He is haveing the equipment wired for this voltage.
I install and work on these all the time. They are also used in the screen printing business. Most rated at 80 amps will be served by a 100 amp service, but always go on the name plate rating. A disconnect should be installed at the machine. BTW 240v 3ph service is the norm here in Houston TX.
I have also dealt with UV Dryers, along with UV Ovens, in several Design-Build Projects (mostly on the "Design" side of the Projects). The Lamps on a few "Older" UV Dryers were similar to the High Pressure Mercury HID Type Lamps used in 10KW Tanning Beds (Quartz Envelopes with fixed Conductor Leads).
As described by others in this Thread, refer to the Equipment's Nameplate FLA (or better yet, MCA), and design the Branch Circuit from the Load indicated per Nameplate.
Sidenote: Having a 240V 3 Phase Delta System available from the Utility, is so nice to have at the Service Equipment, when the Client's Equipment is rated 230-240VAC 3 Phase. Otherwise, such Equipment is connected to an SDS (Transformer with 240V 3 Phase Delta Secondary), and that SDS is either Corner Grounded or Center-Tap Grounded. I prefer Center-Tap Grounding.
Scott " 35 " Thompson Just Say NO To Green Eggs And Ham!