TECNA
S.p.A.
ITEM
TE700 Instruction
Manual
2.6 –
CONSTANT ENERGY OPERATING MODE (ENE)
With a constant energy control unit, all the settings are made as for conventional control units
except for the ENERGY parameter and the welding time parameter, where a set rating is not
required but minimum and maximum ratings are set.
The inverter constantly adjusts the welding current to match it with the set value. During the
welding operations, the inverter detects the real effective value (RMS) of the welding current,
the non-inductive component of the voltage at the electrodes in volts and the welding duration
in mS. The product of I x V x time gives the thermal energy produced during welding,
expressed in joules (W x sec).
Since the energy subtracted by conduction and that dissipated between the external sheets
and the electrodes, reduce the precision of the energy measured, it is advisable to weld with
short timings and high electrode force. Therefore it is important, for good execution of the spot
quality control, that the welding machine it is applied to has adequate specifications relating to
power, electrode force and welding current for the execution of high A and B class spots.
To ensure correct use of the control unit in this working mode, we recommend following the
procedure below step by step:
1. adjust the welding pressure, the welding current and the diameter of the
electrodes according to the traditional tables for the execution of the required
welding.
2. disable the stepper function or the dressing function if activated.
3. set AUTORETAIN ON
4. set the control unit to work in constant current mode.
5. carry one spot weld out and verify that it is satisfactory.
6. read the total developed energy value on the control unit.
7. set the control unit to work in constant energy mode.
8. set the energy value read in the ENERGY parameter of the work program.
9. adjust the minimum time (T. MIN. WELD.) equal to the number of mS required to
carry out the spot with the new electrodes.
10. adjust the maximum time (T. MAX. WELD.) equal to a number of mS that will not
damage the piece to be welded.
ENERGY TREND READINGS DURING WELDING
0
200
400
600
800
1000
1200
1400
0
2
4
6
8
10
12
14
mS
E
n
e
r
g
y
TABLE WITH CONSTANT ENERGY OPERATIONG MODE PARAMETERS
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