Croma24 Service Manual

also constantly monitors the media during printing to determine if the media has run out.

If no paper is sensed, the paper sensor sends this information to the MPCB, which immediately begins an ‘out of paper’ subroutine. This subroutine starts the LEDS on the printer to blink (green blinks slow while yellow blinks faster.) It also informs the host computer of the situation and stops the printer from printing until more media is loaded.

The sensor also checks for the size of the media loaded so it can determine the proper printing parameters.

Power Supply

An internal UL recognized switching power module supplies power for the Croma24 printer. It provides a constant 5 VDC and 24 VDC output from input voltage in the range of 90-264 VAC. The 24 V supply is used for: the stepper controller (which advances the paper); the servo controller (which moves the Carrier); and power to fire the inkjets. The 5V supplies power to the logic circuits.

The power supply is fused using a 2 A 250 V fast blow type fuse.

The outputs share a common ground which is isolated from earth ground within the supply itself. Earth ground and DC ground are connected external to the power supply.

The power supply will shut down under overload/short circuit condi- tions on any output over the full range of input voltage. Overvoltage protection is 20%-30% above nominal for the 5 V and 24 V outputs.

System Grounding

Due to the amount of plastics used in the manufacturing of the printer, a system of grounding the metal assemblies to each other is required. If no common ground was in place, the potential of electric shock could exist due to static voltage buildup on the individual assemblies. The system grounding network ensures that all metallic assemblies have the same ground potential. Figures 2-11 and 2-12 show how the ground straps are implemented on the printers.

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Theory of Operation

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Integra CROMA24 service manual Power Supply