Version February 2020
16
EN
HST 300 Smart User’s Manual
O . M . I . S . A . S r l
Via Verga 9/11
20845 Sovico (MB), Italy
to keep the current report data in memory. They can then
be printed off once again.
Important
Make a habit of handling the internal storage as
described at the beginning of Sect. 8, to maintain
data integrity and avoid any inadvertent deletion
of the reports in memory.
9
Dedicated Welding Unit Information
9.1 Displaying Characteristics of the Welding Unit
The key technical information on the welding unit itself is
displayed by pressing the
ð
key at the “Enter Fitting Code”
screen. They are the software version, the serial number
of the unit, the date of the next scheduled maintenance,
and the number of currently available, unused reports. To
quit this screen, press the STOP/RESET key.
If the scheduled service is overdue, a service due message
appears on the screen as soon as the unit is plugged into
the mains or generator power supply. This message has to
be acknowledged by pressing START/SET.
9.2 Measuring Resistance
When the START/SET key was pressed to initiate a welding
process, the resistance value of the fitting is measured and
compared to the value entered as part of the read fitting
code. If the gap between the two values is smaller than
the acceptable tolerance given in the code, the welding
process starts. If the gap is greater than the preset tol-
erance, the welding unit aborts welding and displays a
“Resistance Error” message. Furthermore, it displays the
actual resistance value measured for the connected fitting.
The reason for a resistance error may be poorly contacting
and/or worn connection terminals. Therefore, if this error
occurs, check them for proper fit and, if worn, replace
them with new ones.
9.3 Overheating Switch
The welding process aborts if the temperature of the
transformer in the welding unit is too high. The overheat-
ing circuit breaker for the transformer stops the welding
if the temperature reading is too high and the remaining
welding time is longer than 800 seconds. The display and
the welding report will show an “Overheated” message.
