Frequently Asked Questions

Denyo United Machinery - Frequently Asked Questions(FAQ)

General Information

How is Denyo different from other brands?

Purchasing Denyo isn’t just buying a machine; instead, you are being welcomed into a bustling world of opportunities, with the right pipelines for your business to grow and increase exponentially. Our superior machines are built to perfection through a unique integrated production process and are able to go on and on without disruption where other competitors/imitators falter and fail, standing the test of time in the harshest of environments and under the most challenging conditions.

Where can I purchase Denyo product?

In Denyo United Machinery, we make the direct sale with potential end-users. Comprising an active usage of Denyo products in over 130 countries worldwide, we are constantly bridging our partners and dealers over the world to fulfil the increasing demands for Denyo generators and related equipment across the region. Find out Denyo authorised dealer in your country.

Do I need a generator to power an outdoor event? If so, what would you recommend?

Generators are mandatory for an event that takes place outside, and to avoid any technical faults – you’ll need a reliable source of power. But first, you will need to figure out the Output Rating (kVA) you will need for all the items that you plan on using with the generator, also including the dimensions and other requests you may have. Based on the specifications provided, our experienced staff will then proceed to recommend the most appropriate generator from our fleet of machines.

Can I purchase spare parts from you?

Yes you can. We operate the regional centre for genuine parts and accessories to Denyo’s full range of generators and other equipment, providing you with consistent inventory availability to ensure speedy replacement that gets you back on track in no time.

Can I request servicing of my Denyo machine?

Yes you may. We provide service and maintenance, as well as parts replacement for all Denyo equipment. Kindly contact us for more information.

Do you provide equipment rental?

Unfortunately no, we do not provide any form of rental services.

Engine Generator Related

What is the difference between direct current and alternating current?

If the two poles of a battery are connected with a lead wire, the current will flow from plus pole to the minus pole. Thus, the current flowing in a single direction is called the direct current. Oppositely, the current with periodically alternating flow directions is called an alternating current The flow direction of electricity supplied to a home is alternating several tens of times per second. Such electricity is called an alternating current.

The alternating current is featured with ease of varying the voltage different from the direct current. The electricity was supplied in a direct current when the electricity business started, but the alternating current has been in its prime by the emergence of alternating current generator.

What is the difference of 50 Hz and 60 Hz?

The flowing direction of an alternating current is periodically reversed. The frequency is the number of cycles of reversing per 1 second, and the unit is Hertz (Hz).

The electricity used in Japan is the alternating current, 50 Hz in eastern Japan and 60 Hz in western Japan. Attention has to be paid on frequency because some of the electrical appliances are not operable if the frequency is wrong. For example, not only the brightness and lifetime of a fluorescent lamp and mercury lamp will be influenced, but also a fire may be caused due to heating. Furthermore, the speed of some of the devices equipped with a motor may vary according to the frequency.

What is the difference between single-phase and three-phase?

The electricity supplied to home has the 100 V or 200 V single-phase 3-wire electrical circuit and is used with electrical appliances (2-wire) of 100 V or 200 V. However if a large amount of electricity is used, three-phase (3-wire) electricity is used. This is because the three-phase alternating current will reduce the wiring cost, and a simple motor (induction motor) can be used.

Engine Welder Related

There is no output (AC/DC) from my Denyo Welder. What should I do?

This happen when a certain component is burnt due to overloading of the machine – commonly occurs on the Control Board, Reactor or Transistor of the Control Unit 35B. This will happen when the usage guidelines are not followed and thus lead to malfunction. When faced with this problem, do send in your faulty unit for our technician to conduct a thorough inspection, and to proceed with repairs of the welder.

What is the difference between the constant current characteristic and the drooping characteristic?

Constant Current Characteristic : there is no current fluctuation with the arc voltage fluctuation with the arc voltage fluctuation while welding. This results in a uniform welding bead. There is less likelihood of a broken arc because there is no fluctuation in welding current caused by fluctuation in arc length through an unsteady hand while welding. Accordingly, it is regarded as a characteristic that prevents defective welding. Furthermore, it facilitates welding with a set current not influenced by cable drop in the welding cable.

Drooping Characteristic: there is a decrease or increase in welding current dependent on welding output voltage fluctuation. This causes non-uniform penetration of beads due to current fluctuation against arc voltage fluctuation caused by unsteady hands, etc., while welding if the welder is inexperienced. Additionally, it may lead to a defective weld such as slag inclusion at the moment that welding current decreases. It is, therefore, a characteristic which makes the arc difficult to control. However, it depends on the welder as well: variation in arc length will influence welding current through the variation in arc voltage. Accordingly, an adjustment may be made on incoming heat through the operation of the welding rod, the bead width and depth, or drooping prevention with fine manual adjustment. Short circuit current in excess of setup current occurring at the start of the arc improves both the arc starting characteristic and the unsteady arc. Because of the characteristic, a welding current drop will occur due to the cable drop while welding.

What are the precautions of handling welding materials?

For the perfect performance of welding material, there are some handling and storage precautions. First, coated electrodes should be handled carefully. Do not throw or drop, because the coating agent may be dislodged by a strong shock. The raw materials such as minerals are bound using liquid glass. If left in a location where rainwater splashes or a location with high humidity, cavity defects such as pitting may occur.

A wire spool for CO2 arc welding is made of plastic resin and is vulnerable to shock; if it is thrown or dropped, the wire will be pinched by a deformed spool or become inoperable through a broken spool. Holding the spool flange will cause a pinched wire; carefully hold the inside of the barrel. If moisture adheres to the wire, the wire will rust and cause imperfect feeding or cavity defects. Store and handle carefully to avoid wetting by rainwater.

Engine Compressor Related

Why is the discharged airflow represented by the intake airflow?

The flow rate of air sucked by a compressor for a certain period of time is called air capacity, represented as Q [m3/min]. It is commonly called as gas volume, but it is called as air capacity only for the case where the air is sucked. For the case of a fan, it is also called as airflow.

For the case of compressor, even when air is used with a certain amount of pressure on the discharging side, the air capacity on the discharging side is not used, but the air capacity on the intake side of compressor is used with the conversion using the temperature, pressure, and humidity on the inlet. When the term “air capacity” is used, it means the intake air capacity. Any gases change their volume substantially depending on the pressure and temperature, so if any discharged air capacity is used, it is always necessary to indicate its pressure and temperature on that place.

Air capacity in intake status means the status of wet air at the condition of 20oC of temperature, 760 mmHg of absolute pressure, and 65% of humidity. Air capacity on standard status means the dry air of 0oC of temperature, 760 mmHg of absolute pressure, and 0% of humidity (normal air capacity). Roughly, normal air capacity (Nm3/min) = air capacity on brochure (m3/min) x 0.85

It is difficult to start up the engine of the compressor during the cold season. What should I do?

Make sure to use the start-up discharge valve for easier engine start-up. Also, make sure to use the engine oil with appropriate viscosity suitable for different temperature.

Why must we drain water from the compressor oil before starting up the engine?

If water stands in the compressor, compressor oil will emulsify to lose its function which results in the malfunction of bearing in compressor (air end), the corrosion of various pipes, and other troubles. For this reason, make sure to use designated compressor oil and use the bypass valve to control the temperature of the appropriate range. Release water content with the discharge air to the outside of the machine so that water content won’t stand within the compressor.