Unitor UWI 203 TP - User Manual

ukirbyAug 1, 2025

What to do if Unitor Welding System has no output and yellow warning light?

D
Dawn VelasquezAug 1, 2025
If your Unitor Welding System shows no output and a yellow warning light, it could be due to several reasons. The voltage protection might be activated because the input voltage is outside the range of 342 - 484V. Thermal protection could be activated if the duty cycle is too high; in this case, wait for the machine to cool down, then weld with more breaks or at a lower current. Also, check for obstructions hindering cooling airflow, heat development in loose electrode holder or ground cable connections, a broken fan (repair or replace if needed), or excessive dirt in the power source compartment (clean it out).

Summary

General Description

Identify Components

Lists and visually identifies the main components of the Unitor Welding Inverter UWI 203 TP.

Technical Data

Type of Welding Machine

Specifies the machine as a three-phase static transformer rectifier frequency converter with DC output.

Supported Processes

Lists supported welding processes: MMA (Stick electrode / SMAW) and TIG (GTAW).

Safety Marking

Explains the 'S' safety marking indicates suitability for areas with increased electric shock hazard.

Duty Cycle Explanation

Explains duty cycle as percentage of 10 minutes at rated load and conditions for overheating.

Voltage Definitions

Defines No-load voltage (Uo), rated reduced no-load voltage (U1), and Arc voltage (U2).

Primary Connection and Cooling

Details primary connection requirements, input voltage, current, and cooling method.

Protection and Insulation Classes

Explains IP23S protection class and I.CL.H thermal insulation class.

Applicable Standards

Lists applicable standards like EN 60974-10 and EN 60974-1, and CE marking.

Dimensions and Weight

Lists dimensions (Height, Length, Width) and weight of the welding machine.

Installation Instructions

Suitable Location Selection

Advises locating the welder in a dry area with free air circulation, minimum 50cm space.

Avoid Tilting

Instructs to place the machine on a secure, level surface, max 15° tilt.

Assembly and Connections

Illustrates the connection of primary cable, ground cable, and electrode holder.

Polarity Selection Guidance

Advises selecting polarity based on electrode package and job, TIG welding negative to torch.

Front and Back Panel Overview

Control Panel Description

Describes front panel controls and indicators: power warning, thermal protection, process selection, current adjustment, arc force.

Primary Cable Specification

Describes the primary cable: 4 core 2.5mm², 3m long.

Missing Phase Warning Light

Explains the missing phase warning light indicates a power supply phase failure.

Welding Procedures

MMA (SMAW Stick Electrode) Welding

Explains how to select MMA, connect ground, select polarity/amperage, and strike an arc.

Hot Start Feature

Explains automatic Hot Start for easier arc striking and reduced electrode sticking.

TIG (GTAW) Welding

Explains how to select TIG, connect torch and ground, and the arc starting process.

Routine Maintenance Schedule

Electrical Connections and Cables

Maintenance of primary plug, socket, cables, and connectors for optimal performance.

Welding Accessories and Components

Maintenance of welding current sockets, electrode holders, ground clamps, and remote controls.

Internal Cleaning and Label Checks

Procedures for cleaning internal dust and dirt, and checking/replacing labels.

Troubleshooting Guide

No Output, No Warning Light, Fan Not Running

Addresses issues with no output, no warning light, and the fan not running.

No Output with Yellow Warning Light

Addresses issues of no output accompanied by a yellow warning light.

No Arc with No Warning Light

Addresses issues where there is no arc and no warning light is displayed.

Unstable Arc Issues

Addresses problems related to an unstable welding arc.

Available Accessories

Cable Extension Accessories

Lists accessories for extending welding cables, including cable and connectors.

Stick Welding Accessories

Lists various accessories for stick (MMA) welding, such as face shields, filter glass, gloves, electrode holders.

TIG Welding Accessories

Lists accessories for TIG welding, including torches, regulators, and flow control meters.

TIG Torch T-200 Components

Details the individual components of the TIG torch T-200, including back-caps, collets, nozzles, and electrodes.

Safety Instructions

General Arc Welding Hazards

Outlines general dangers associated with arc welding processes.

Electric Shock and Grounding Precautions

Details risks of electric shock, importance of power disconnection, and proper grounding.

Equipment Maintenance and Safe Practices

Emphasizes using maintained equipment, safe practices, and residual DC voltage caution.

Fume and Gas Hazards

Addresses dangers from welding fumes and gases, recommending ventilation and respirators.

Arc Ray and Skin Burn Hazards

Details risks from arc rays causing burns and the necessity of protective eyewear and clothing.

Fire and Explosion Risks

Covers fire and explosion hazards related to welding, emphasizing safety in the work area.

Eye Injury from Flying Metal

Warns about eye injuries from flying metal and slag, recommending safety glasses.

Gas Buildup Hazards

Explains the dangers of gas buildup, especially in confined spaces, requiring ventilation.

Hot Parts and Cooling

Caution against touching hot parts and importance of cooling periods before handling.

Pacemaker and Noise Hazards

Safety advice for pacemaker wearers and regarding noise-induced hearing damage.

Gas Cylinder Safety

Discusses risks associated with gas cylinders and proper handling, storage, and usage.

Installation and Operational Precautions

General precautions for installation, operation, and maintenance, including placement and wiring.

Unit Handling and Overuse Warnings

Advice on safe unit lifting, handling, and avoiding overheating due to overuse.

Component and Wire Handling Safety

Warnings about static discharge (ESD), moving parts, and welding wire hazards.

Interference from HF Radiation and Arc Welding

Addresses interference caused by HF radiation and arc welding, with mitigation strategies.

Electromagnetic Field (EMF) Information

Discusses EMF effects and provides guidelines for reducing magnetic field exposure.

Brand	Unitor
Model	UWI 203 TP
Category	Welding System
Language	English

Brand

Unitor

Model

UWI 203 TP