DSP 500 PS

Diesel Engine driven welder - PERKINS 404D-22G Engine -  Three-phase asyncronous alternator  - Three-phase generation 16 kVA - Single-phase generation 12 kVA - Max welding current: 500A

The engine-driven welder DSP 500 PS is a professional multi process machine with digital adjustment of the welding parameters DSP (Digital Signal Processor) and welding circuit with Chopper 
System (high frequency 20 kHz) capable of delivering up to 500 A with a duty cycle of 60%.

Equipped with a Perkins series 400 water cooled diesel engine and an asynchronous alternator, it can be used simultaneously as a welder and as a three-phase and single-phase electrical generator up to 20 kVA.

Thanks to the lower engine speed (1500 rpm) it is suitable for continuous operation in all conditions.
Designed to meet the requirements of professional welding in direct current, a selector switch allows the operator to choose between 5 different welding programs:

  1. LIFT ARC TIG – TIG welding by controlling start-up in "Lift Arc" mode. The arc begins with a simple contact of the electrode on the workpiece and lifting the tungsten electrode from the workpiece initiates the arc without inclusion.
  2. MMA STICK (3 PROGRAMS) – Specific for MMA ELECTRODE (CC) welding, they offer three different levels of arc force, with increasing short-circuit currents including cellulosic.
  3. MIG MAG – Dedicated to SOLID WIRE OR FLUX-CORED WELDING, providing employing a constant voltage (CV) welding process with optional MOSA WF4 Wire Feed Unit.

The DSP 500 PS is a super-silent engine-driven welder with compact canopy, suitable for a wide range of applications, including large metal fabrications oil pipelines and construction sites.

In according with CE regulation

More Information


Model Fuel Starter Output Cylinders / Displacement Speed Cooled
Perkins 404D-22G Diesel Electric 20.3 kW (27.6 HP) 4/ 2216 cm3 1500 rpm Water

Technical Features

sample powersafe WELDING

SMAW (STICK)/ GTAW (TIG) CC (Costant Current)
  • Current range: 10 ÷ 500A
  • Duty cycle: 500A - 35%, 450 A - 60%, 400A - 100%
  • Open circuit voltage: 62 V

GMAW (MIG)/ FCAW (FLUX CORED) CV (Costant Voltage)
  • Voltage range: 16 ÷ 40V
  • Duty cycle: 450A 60% - 400A 100%
  • Arc multi-process welder:
    - SMAW: Shielder Metal Arc Welding (Stick)
    - GTAW: Gas Tungsten Arc Welding (TIG) - Contact starting
    - GMAW: Gas Metal Arc Welding (MIG)
    - FCAW: Flux Cored Arc Welding (Flux Cored)
  • High frequency digital control of welding current and voltage
  • Specific welding programs for cellulose electrodes
  • Double welding output (HALF/FULL - 50% / 100%)
  • Digital Ammeter/voltmeter welding

  • Dry weight: 750 kg
  • Dimensions: 1720x980x1110 mm
  • Measured acoustic power LwA (pressure LpA): 91 dB(A) (66 dB(A) @ 7 m)
  • Guaranteed acoustic power LwA (pressure LpA): 92 dB(A) (67 dB(A) @ 7 m)

  • Auxiliary output 400Y/230I/48I: 1x400V 32A 3P+N+T CEE - 1x230V 32A 2P+T CEE - 1x230V 16A 2P+T CEE
  • Auxiliary output 400Y/230I: 1x400V 32A 3P+N+T CEE - 1x230V 32A 2P+T CEE - 2x230V 16A 2P+T CEE
  • Auxiliary output 400Y/230I/110I CTE: 1x400V 32A 3P+N+T CEE - 1x230V 32A 2P+T CEE - 1x110V 32A 2P+T CEE - 1x110V 16A 2P+T CEE
  • PL version: version with polarity change and VRD - Voltage reduction device

DSP Program

sample powersafe TECHNOLOGY

The acronym DSP, which is referred to this line of MOSA welders, stands for "Digital Signal Processor", and identifies the fact that the regulation of the welding parameters is performed by means of a digital technique. More precisely, in the DSP controller reside the programs which perform the regulation of the different welding processes supported.

The implementation of the control is accomplished by a power converter of the "Chopper" type (Chopper System), which operates at high frequency (20 kHz).

The high frequency conversion allows to obtain superior welding performances in comparison with more conventional techniques at low frequency.


Via a rotary selector you can choose between 5 different welding programs.

  1. LIFT ARC TIG – This program performs  a TIG welding with a "Lift Arc" start. With this feature the arc is started simply by touching the piece, without scratch.
  2. STICK (3 PROGRAMS) - They are specific for the electrode welding (CC), being characterized by three different arc force levels with increasing short circuit current from 1 to 3.
  3. MIG MAG – It is dedicated to WIRE welding, WITH GAS or FLUX CORED. This welding process is performed at constant voltage (CV).

The front panel of the DSP control unit is provided with a military type circular connector which can be connected to a MOSA remote control unit or wire feeder, for MIG MAG. When plugging an external connector the control is automatically switched from the front panel knob to the knob on the remote unit. All the machines of this series are equipped with digital meters to monitor the welding current and voltage. The software of the control unit, depending on the version of welder on which it is installed, can handle various functions, including:

a) Power Optimizer - A function that prevents overloading of the engine during welding
b) VRD - (Voltage Reduction Device) a function that reduces the open circuit voltage to a safe value when  not welding
c) Reverse polarity – In the models where this function is present , a switch on the panel commands the contactor which implements the polarity reversal.

The DSP controller also implements some security features:
  • Chopper converter overtemperature
  • Overcurrent during welding (due to failure or malfunction)
  • Current sensor not connected
  • Malfunction of the supply voltage