CPM Down Control

This machine employs several CPM down modes to maintain the quality of printed images and to optimize and protect the operation of the machine

High-Temperature CPM Down

When paper narrower than the width of the heated surface of the hot roller passes through the fusing unit, the amount of unabsorbed heat at the ends of the hot roller causes the fusing unit to become abnormally hot. As soon as the machine detects such a rise in temperature, it will lower throughput and then regulate the high temperature inside the fusing unit.

After printing continuously more than 60 seconds, the fusing thermistor (TH1) starts to check the temperature at one-second intervals. Based on these temperature readings the machine will determine the appropriate CPM down level. The CPM down levels are described below.

Low-Temperature CPM Down

If the fusing lamps cannot keep pace with the print job and are unable to maintain the target fusing temperature, throughput is slowed down to make it easier to maintain the target temperature.

The fusing thermistor (TH1) checks the temperature every 10 sec. If the temperature reading is down by the critical temperature setting for SP1-124-001 (default: -25°C), the CPM level is lowered one step, and if the temperature reading is up by the critical temperature setting for SP1-124-002 (default: -5°C), the CPM level is raised one step.

CPM Down for Curl Reduction Mode

If the Curl Reduction Mode is selected in the User Settings for a print job, at the start of throughput the following conditions apply.

Low Power CPM Mode (200V Model Only)

With a low voltage power supply, the CPM down rate set at 33% automatically at the start of throughput.