D-3

MAINTENANCE

D-3

 

 

 

METER CALIBRATION ADJUSTMENT

The Precision TIG meter circuits are factory calibrated for the accuracy of the ammeter and voltmeter (see Section B Panel Control Functions), and should not need adjustment. However, the factory trimmers are accessible inside the control box (see Section D Component Access):

•The Meter Board, located on the front panel of the machine, is digital and has no calibration capability.

•Ammeter Calibration Trimmer (R5) is located on the Control PC Board (left of center near the top of the board). This trimmer adjusts calibration of the ammeter circuit to the digital panel Meter, so it should be checked after the Digital Meter check above. The ammeter calibration is checked as follows:

1.Set to TIG mode with DC- polarity and LOCAL control. Without closing the arc start switch, preset the Maximum Output panel control so the panel digital Meter reads about 200 amps.

2.Using a DC (avg.) test ammeter with at least 1% accuracy at up to 300 amps, connect it to measure the DC current through a short weld cable shorting out the WORK (+) to ELECTRODE (-) studs on the front stud panel. Remove the TIG torch, if connected.

3.Close the arc start switch just long enough to compare the panel Meter reading to that of the test ammeter. The short circuit current readings should match within 4%+/-2A. If not, adjust the trimmer so that the panel meter accuracy is corrected.

•Voltmeter Calibration Trimmer (R2) is located on the Control PC Board (right of center near the top of the board). This trimmer adjusts calibration of the voltmeter circuit to the digital panel Meter, so it should be checked after the Digital Meter check above. The voltmeter calibration is checked as fol- lows:

1.To prevent maximum OCV output (which is not precise for voltmeter checking) discon- nect the SCR gate lead plug from recepta- cle J4 on the lower left corner of the Control PC board.

2.Set to TIG mode with DC- polarity without closing the arc start switch.

3.Using a DC (avg.) test voltmeter with at least 1% accuracy at up to 100 volts, con- nect it across the WORK (+) and ELEC- TRODE (-) studs on the front stud panel. Remove the TIG torch, if connected.

4.Press the DISPLAY panel switch to V (volts) position, then close the arc start switch just long enough* to compare the panel Meter reading to that of the test volt meter. The open circuit voltage readings (about 50vdc) should match within 3%+/-1V. If not, adjust the trimmer so that the panel meter accura- cy is corrected.

* If switch is held closed longer than about 15 seconds the Precision TIG will shut down to protect internal holding resistor from overheating.

UNDER-COOLER SERVICE

The required maintenance and service instructions for the Under-Cooler are provided in the operatorʼs manu- al (IM723) provided with the Under-Cooler Cart.

PRECISION TIG 275

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Lincoln Electric 275 manual Meter Calibration Adjustment, UNDER-COOLER Service
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275 specifications

The Lincoln Electric 275 is a versatile multi-process welding machine that stands out for its advanced features and robust performance. Designed for both novice and experienced welders, the machine offers MIG, TIG, and stick welding capabilities, making it a valuable tool for a variety of applications.

One of the main features of the Lincoln Electric 275 is its power output. With an impressive selection of amperage settings, it can deliver between 25 to 275 amps, making it suitable for both thin and thick materials. This flexibility allows users to work on projects ranging from automotive repairs to industrial fabrication.

The machine utilizes inverter technology, which significantly enhances its efficiency and reduces power consumption. Inverter welders are known for their lightweight design and compact size compared to traditional transformer-based welders. This portability makes the Lincoln Electric 275 easy to transport to job sites, catering to both professional and hobbyist welders who require mobility.

Another defining characteristic of the Lincoln Electric 275 is its easy-to-use interface. The digital display provides clear readings, allowing users to effortlessly adjust settings for optimal performance. Additionally, the machine features a user-friendly control panel with distinct knobs for regulating voltage and wire feed speed, assisting welders in achieving precise welds.

The Lincoln Electric 275 is also equipped with advanced arc technologies. Its built-in arc control enhances the stability of the welding arc, resulting in a smoother, more consistent weld. Furthermore, the machine offers synergic controls that automatically adjust the voltage and wire feed speed based on the selected material and thickness, making the welding process more intuitive and reducing the margin for error.

Durability is another hallmark of the Lincoln Electric 275. Constructed with high-quality materials, the machine is built to withstand the rigors of daily use in demanding environments. Its design also incorporates efficient cooling mechanisms to prevent overheating during prolonged operations, ensuring longevity and reliability.

In conclusion, the Lincoln Electric 275 is a powerful and adaptable welding machine that combines advanced technology with user-friendly features. Its multi-process capabilities, inverter technology, and robust construction make it an essential tool for both professional welders and DIY enthusiasts. Whether tackling intricate projects or heavy-duty tasks, the Lincoln Electric 275 proves to be a reliable choice that does not compromise on performance.
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