Riland ARC 250G - User Manual

Questions and Answers

S
Sandra LongAug 10, 2025
Why is there too much spatter during MMA welding with my Riland ARC 250G Welding System?
- A
  Amber JuarezAug 10, 2025
  If you're experiencing excessive spatter during MMA welding with your Riland Welding System, it might be due to incorrect output terminal polarity. Try changing the polarity to resolve this issue.
E
Ethan HoustonAug 15, 2025
What to do if the power switch on my Riland ARC 250G Welding System doesn’t work?
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  kellersaraAug 15, 2025
  If the power switch on your Riland Welding System isn't working, the power switch itself may be broken. Also, a broken three-phase rectifier bridge could be the cause, consider replacing it. Finally, check for any short circuits inside the machine.
M
Mary BarnesAug 20, 2025
Why is the welding output current erratic on my Riland ARC 250G?
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  Michael ArnoldAug 21, 2025
  If you're experiencing erratic welding output current or the potentiometer seems out of control on your Riland Welding System, the potentiometer may be damaged. Also, check all connectors, especially plugs, for poor contact.
R
richard81Aug 26, 2025
What to do if my Riland Welding System has no welding output but the meter and fan are working?
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  George EverettAug 26, 2025
  If your Riland Welding System's meter and fan are working but there's no welding output, check for poor contact in all machine components. Inspect the output terminal connector for damage. If these steps don't resolve the issue, the control board may be damaged.
C
ckingAug 30, 2025
Why is the abnormal indicator on my Riland ARC 250G lit?
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  meganfergusonAug 30, 2025
  If the abnormal indicator is on, but the fan is working and the meter is normal on your Riland Welding System, the IGBT or the rectifier of quick recovery might be damaged. Another possible cause is a broken control board. The feedback circuit may also be at fault.
R
Ray BuckSep 4, 2025
How to troubleshoot a Riland ARC 250G with no meter display, fan, or welding output?
- L
  lauren86Sep 5, 2025
  If the meter isn't displaying, the fan isn't working, and there's no welding output from your Riland Welding System, first ensure the power switch is off and then on. Verify that the power source connected to the input cable is functioning correctly. Also, make sure the input voltage is 3 phase.

This document describes the ARC 250G/315G/400G series of inverter welding machines, which utilize advanced inverter technology and high-power IGBT components to convert 50/60Hz frequency up to 15KHz, then reduce voltage, commutate, and output high-power voltage via PWM technology. This design significantly reduces the weight and volume of the main transformer and increases efficiency by 30%, marking a revolution in the welding industry.

Function Description:

The ARC 250G/315G/400G welding machines are rectifiers designed to provide a strong, concentrated, and stable arc. They offer quick response when the stick and workpiece short, making it easier to design different dynamic characteristics and allowing for adjustments to make the arc softer or harder. These machines are effective, power-saving, compact, and feature a stable arc, good welding pool, high no-load voltage, and excellent force compensation capacity, making them multi-purpose. They are capable of welding stainless steel, alloy steel, carbon steel, copper, and other colored metals. They can be used with electrodes of various specifications and materials, including acidity, alkalinity, and fiber, and are suitable for high-altitude environments, open-air work, and both indoor and outdoor decoration. The series is particularly well-suited for welding tubes, boilers, vacuum pressure vessels, or other high-quality welding applications where perfect welding quality is essential. They also provide sufficient no-load voltage and output ability, making them ideal for long cable welding.

Important Technical Specifications:

The ARC 250G, ARC 315G, and ARC 400G models share many core specifications but differ in output capacity and physical dimensions.

Power Voltage: All models operate on Three Phase AC 400V±15%.
Frequency: 50/60 Hz for all models.
Rated Input Current:
- ARC 250G: 14.4 A
- ARC 315G: 19.7 A
- ARC 400G: 27.6 A
No-load Voltage:
- ARC 250G: 66 V
- ARC 315G: 69 V
- ARC 400G: 68 V
Output Current:
- ARC 250G: 20-250 A
- ARC 315G: 20-315 A
- ARC 400G: 40-400 A
Rated Output Voltage:
- ARC 250G: 20.8-30 V
- ARC 315G: 20.8-32.6 V
- ARC 400G: 21.6-36 V
Duty Cycle (0-100%): 60% for all models.
Efficiency: 85% for all models.
Power Factor: 0.93 for all models.
Insulation Grade: F for all models.
Housing Protection Grade: IP21 for all models.
Weight:
- ARC 250G: 17.5 Kg
- ARC 315G: 20 Kg
- ARC 400G: 22 Kg
Dimensions (mm):
- ARC 250G: 455×202×372
- ARC 315G: 485×234×425
- ARC 400G: 515×262×468

Usage Features:

The machines are equipped with power voltage compensation, allowing normal operation even when the power voltage fluctuates within ±10% of the rated voltage. For long cable usage, a larger section cable is recommended to prevent voltage drop and maintain performance.

Installation: Ensure the machine's intake is not blocked. Connect the housing to the ground using an inducting cable of at least 6 mm². Correctly connect the arc torch or holder and the earth clamp, paying attention to polarity. DC welding machines offer two connection methods: positive connection (holder with "-" polarity, workpiece with "+" polarity) and negative connection (workpiece with "-" polarity, holder with "+" polarity). The appropriate method should be chosen based on working demands to avoid unstable arc, spatters, or conglutination.
Operation: After opening the power switch, the screen displays the set current, and the ventilator starts. Welding current and arc-striking push knobs allow adjustment for specific welding demands. Recommended current ranges for different electrode sizes are provided: φ2.5 (70-100A), φ3.2 (110-140A), φ4.0 (170-220A), and φ5.0 (230-280A). The arc-striking drive knob helps adjust welding function, especially at low currents, providing powerful energy and push current.
Safety Features: An anti-shock device (VRD) can be installed. When the VRD switch on the back panel is "ON," the VRD indicator lights up, and the no-load voltage is reduced to less than 15V for safety. When "OFF," the no-load voltage is 60-70V.
Remote Control: If a remote control device is coordinated, ensure its switch is in the "ON" position and the plug is firmly inserted. If not using remote control, the switch should be "OFF" to allow panel adjustments.
Hot Initiation: Provides heavy current for a perfect effect and easier striking.
Environment: The machine operates in dry environments with humidity up to 90%, and ambient temperatures between -10°C and 40°C. Avoid direct sunlight, dripping water, dusty areas, corrosive gases, and strong airflow.
Protection: The machine includes protection circuits for over-voltage, over-current, and over-heat. If these limits are exceeded, the machine will automatically stop. An indicator light turns red if the machine overheats due to exceeding the duty cycle. In such cases, the machine should be allowed to cool down with the fan running until the indicator light turns off.

Maintenance Features:

Regular maintenance is crucial for the longevity and performance of the welding machine.

Dust Removal: Regularly remove dust using dry, compressed air. In environments with smoke and pollution, cleaning should be done monthly. The pressure of compressed air must be within a reasonable range to avoid damaging internal components.
Circuit Check: Periodically inspect the internal circuits to ensure connections are correct and tight, especially plug-in connectors and components. Clean any scale or rust found and re-tighten connections.
Moisture Prevention: Prevent water and steam from entering the machine. If this occurs, blow it dry and check the insulation.
Storage: For long-term storage, pack the machine in its original box and store it in a dry and clean environment.
Dynamotor Connection Warning: Connecting the welding machine directly to a dynamotor can cause damage due to heavy voltage pulses. Only asynchronous dynamotors with steady frequency and voltage should be used. Damage resulting from direct dynamotor connection is not covered under warranty.
Troubleshooting: The manual provides a troubleshooting guide for common issues like no display/output, abnormal indicator light, excessive spatter, or erratic output current. Solutions include checking power switches, input voltage, connections, and components like IGBTs, rectifiers, and control boards. If problems persist after these checks, users are advised to contact the local dealer or after-sales service department. All maintenance and repair operations should be performed by qualified electricians.