Why are laser printers so difficult to power?

Laser printers are a challenge for mobile power applications two reasons: they require a lot of power and, some, are very particular of how �clean� the provided power is. MORE POWER VS LESS POWER: When an inverter shuts down because of overload, it is because the printer requires more power than the inverter can provide. This is mostly related to the type of heater that the printer uses to fuse the toner to the paper. There are two types of laser printer fusers. 1) Halogen Lamp (Hot roller) Older technology Very high inrush current Possible higher idle power due to keeping roller hot to reduce wait time Less expensive and has a shorter life Manufacturers that primary use this heater: Brother Dell Epson Konica Minolta Kyocera Legend Lexmark OKI Samsung Ricoh Xerox 2) Ceramic (Foil) Modest inrush current Newer technology Most common Faster warm-up time More expensive Foil based fusers usually last longer roller based machines Manufacturers that primary use this heater: HP (Marketed as �Instant-On�) Canon (Marketed as On-Demand�) POWER SENSITVITY (MODIFIED VS PURE/TRUE SINE WAVE): When a laser printer gives an error pertaining to the fuser it is because the printer�s engine firmware requires pure sine wave. Modified sine wave inverters can present two types of issues for some laser printers. This relates to an AC zero-crossing signal used by some printers. Some laser printers generate an AC zero-crossing logic signal which is a pulse synchronized to the AC voltage zero crossings. That signal is used in phase control algorithms to throttle a known amount of power to the heater. If the timing between pulses is not what would be expected for a normal sine wave or the power delivered is incorrect because the non-sine wave shape created an incorrect power delivery value the printer will likely throw an error condition. We know that Lexmark laser printers require pure sine wave inverters. However, we have seen some HP laser printers operate fine on modified sine wave inverters.