Microcom 438TM, Operator'S Manual

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Chapter 3 Getting Started
438TM Operator’s Manual - 880049-0113 3-39
is activated, the power supply should shutdown automatically. Once the abnormal condition
resulting in the failure is removed, the power supply should restart accordingly. If over
Voltage Protection is activated, the power supply will shut down. The power supply should
be fully protected against short circuits and automatically recover gracefully.
The output circuits (USB, Serial) may not be power limited. Equipment connected to these
output connectors shall be of the certified type with their own fire enclosure. If a non-
Microcom Corporation supplied power supply is used, it shall be of the certified type and a
limited Power Source.
It is highly recommended that Microcom provide the power supply in order to prevent
damage to the printer or cause the printer not to function properly.
3.12.8 Electrostatic Discharges and Ground Connections
The printer should have a dedicated earth ground connection. Preventing ESD and earth
currents from affecting the printer’s operation requires proper connection to the printer
chassis via a 12 AWG wire to earth ground. The ground wire should be connected to the
printer chassis using a closed loop connector. Measure the resistance with an ohm meter to
ensure proper grounding.
The same ground MUST be used for the printer, printer power supply, and any device (PC,
USB hub, etc.) connected to the printer USB or serial ports. The same AC power circuit
ground location should be used whenever possible for these devices.
If the printer is in a low humidity environment, the use of anti static brushes or tinsel may be
required.
Electrostatic discharges can cause damage to the print head, memory or electronics. This
damage will manifest itself as lost pixels on the print head, memory scrambling,
communication to the printer lost or other issues causing the printer not to function properly.
This damage can be immediate or happen over time.
When working with the USB port, it is imperative that ESD and Ground connections are
adhered to or potential disconnect issues may be encountered. We also recommend
disabling the ability to allow the computer to turn off the USB device under the Power
management.
Example:
1. Open the system Device Manager.
2. Scroll to the Universal Serial Bus Controllers and expand the listing.
3. Open the USB Root Hub’s listed (not the USB 2.0 Root Hub’s).
4. Go to the Power Management tab under the Properties.
5. Uncheck the “Allow the computer to turn off this device to save power”.
6. Select OK and repeat for the remaining USB hubs.
3.13 TOF Sensor
The TOF Sensor is used to detect when media is present and is used in conjunction with the
Top-Of-Form operation. A TOF is when the printer uses the sensor to detect the edge of
the media and retracts the configured distance. See the D121 and D123 commands for
more details regarding the TOF operation.