KERN & SOHN VFS 2T1 Addendum - Manual (Page 12)

EPM205 - Technical reference - Rev. A Page 12
Advanced Printing Systems
3.9. Operating precautions
1- When performing continuous printing, the supply energy should be reduced so that the substrate
temperature, monitored through the thermistor, will remain below 65°C.
2- All strobes signals must be disabled during the power and logic voltage
ON
/
OFF
sequence.
3- Do not touch the connector pins with naked hands.
4- The print-head substrate surface is coated with glass, for this reason, mechanical stresses, shocks, dust
and scratches should be avoided to prevent damage.
5- When the print-head operation is completed, print supply voltage (including the charged voltage with
capacitor) should be reduced to the ground level and maintained until next print-head operation.
6- Avoid condensation, if condensation occurs, do not switch ON the print-head power, until condensation
has disappeared.
7- When plugging in and out of the connectors, avoid using excess force as damage may result (Plug in-out
cycle for this connector should not exceeded 20 times). Do not pick up the mechanism by the connectors.
8- Print quality would become degraded if paper or ink residue were stuck on the heat element area. In this
case, clean the print-head with an applicator and alcohol. Do not use the sandpaper as this will destroy
the heating elements.
9- If sticking sound, is heard while printing, please check and adjust the paper feed mechanism and the
electrical pulse program to eliminate the sound.
10- Make sure the paper does not have high abrasion factor, low sensitivity or abnormal chemicals.
11- To avoid surges and voltage losses, a 47
mF aluminium capacitor between VH and GND is necessary on
customer’s controller board side.
Important precautions
To prevent any dot element damage:
At power up make sure that logic voltage (Vdd) is present simultaneously or before VH.
At power down make sure that VH is at 0 V before removing logic voltage.