Fronius TP 1500, Руководство по обслуживанию

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If a short circuit takes place, there is a
brief rise in the amperage. In order to
obtain a stable arc, the welding current
also increases briefly, in line with the pre-
set dynamic - e.g. from 140 A to 180 A
(see Fig.10).
If the electrode is threatening to sink into
the weld pool, this measure prevents the
weld pool from solidifying, as well as
preventing more prolonged short-circuiting
of the arc. This largely eliminates any risk
of the rod electrode “sticking”.
U
out
140 A max.180 A
92V
65V
40V
20V
Adjustable
short-circuit
dynamic
response
Standard characteristic
for electrode
I
out
(1)
(2)
(3)
Fig.10 Characteristic / operating ranges of the TP 1500
Legend:
(1) Continuous operation
- When the duty cycle is exceeded:
- Power-pack switches off
- “Error” indicator lights up
- Once the cooling phase has elapsed, the power-pack switches back on again
(2) Operation for max. 2 seconds
- If this 2-second period is exceeded:
- Power-pack switches off
- “Error” indicator lights up
- In no-load operation, the power-pack switches back on again
(3) No-load operation
- The sawtooth open-circuit voltage (see Fig.7) is applied to the output sockets
Measuring and
regulating the
parameters
“welding
current” and
“welding
voltage”
(continued)
The TP1500 TIG, TP 1500 RC and TP 1500 power sources are equipped with the Hot-
Start function, which is permanently activated as long as the “rod-electrode welding”
process is selected. As soon as the arc is started, the Hot-Start function increases the
welding current by one-third of the value originally set on the welding-current dial. This
brief increase in the current occurs for a period of 0.5 sec.
Example:
If the pre-set welding current was 90 A, the welding current is increased to 120 A.
Where the pre-set welding current is more than 120 A, the Hot-Start current is limited to
a maximum of 160 A.
Benefits:
- Improved ignition - even when using electrodes with poor ignition properties
- Better base-metal fusion in the start-up phase, meaning fewer fusion defects
- Largely prevents slag inclusions
Hot-Start and
Anti-Stick
functions