Operation Archives - Page 3 of 4 - All About MEAN WELL Power Supplies

What is “Inrush Current”? What will we notice?

At input side, there will be (1/2 ~1 cycle, ex. 1/120 ~ 1/60 seconds for 60 Hz AC source) large pulse current (Ipk 20~100A based […]

Why is the input voltage on the label different from the input voltage in the spec? For example, the specification shows is 88~264 VAC while the label on the power supply says that it is 100~240VAC?

During safety verification process, the agency will use a stricter standard ±10% (IEC 62368 uses +10%, -10% for the product with AC input rated) of […]

What is the difference between -V and COM which are marked on the output side?

COM (COMMON) means common ground. Please see below:nSingle output: Positive pole (+V), Negative pole (-V)nMultiple output (Common ground): Positive pole (+V1, +V2,.), Negative pole (COM)

Can I connect 2 phase 120VAC to a power supply rated for 240VAC input?

If the two phases are 180o out of phase (split phase system), then yes. The resulting voltage will be around 240VAC, so it can be […]

In MEAN WELL’s catalog, we see AC and DC at input, what is it all about?

Due to different circuit designs, the MEAN WELL power supply’s input consists of three types as below: (VAC≒VDC) a. 85~264VAC;120~370VDC b. 176~264VAC;250~370VDC c. 85~132VAC/176~264VAC by […]

How to increase hold-up time?

The hold-up time is the duration between the instant when the input is shut off, and when the output voltage falls below 90% of the […]

What is power good and power fail signals and how can use it?

Some power supplies provide a “Power Good” signal when they are turned on and send out a ” Power Fail” signal when they are turned […]

What is PMBus?

PMBus full name is Power Management Bus is an open standard for digital power management. The physical layer is based on I2C, and PM Bus […]

What are the protection forms of overload/overcurrent?

When current drawn exceeds the rating of the PSU, the protection circuit will be triggered to protect the unit against overload/overcurrent. Protections of overload/overcurrent can […]

What is CAN Bus?

A Controller Area Network (CAN Bus) is a bus standard initially developed for vehicle designed to allow multi-master with priority control without a host computer. […]

Technical Articles