Can I ask the experts here.

I measured my Wall Power output is around 247W. Most of appliances like Computer PSU is only rated for around 230V usage if I am not mistaken. Is the Wall output almost 250V too high. Will it shorten the lifespan or cause damage to equipment?

Are all the wall sockets in your house measured at around 247v constantly? If yes, my guess is your house probably situated near a TNB substation. Although 247v is on the high side, there's no need to be alarmed as all you might experience are fans runs slightly faster, water heater runs slightly hotter etc. What you really need to take notice is if the measurement at the wall power outlets are on the low side (below 220v). Below are examples that causes low supplied voltage :

1. Wiring too old & degraded.
2. Termination or point of contacts oxidation.
3. Using power extension with low quality copper wiring or steel wiring (rare but exist)
4. Sharing the same power outlet with a high power appliance.

Constant low supplied voltage causes electrical appliances to fail prematurely due to overworked & overheated, wiring to catches fire etc.

Any corrections or additional info from experts are welcome.

First of all sorry for the typo , it's 247V (as you already know). On another outlet it's about 245V.

For the 247V outlet, it will fluctuate slightly +/- some decimals. Sometimes it may go to 246V briefly , sometimes 248V briefly.

Since it's borderline high, I am afraid it may go above 250V sometime when not observing. I have experienced computer Motherboard failure quite often, not sure if the high voltage is the cause. Do you think I should get an AVR to play safe?

Thanks for your valuable advice

Are all the motherboards that failed came from the same computer or power supply? Normally if supplied voltage is causing problems, the 1st thing that should be affected is the power supplies & not the motherboard. Is there any other electrical appliances that failed frequently?
Anyway if you suspect the culprit is the supplied voltage, an AVR from a good brand/manufacturer will ensure your electrical appliances gets the voltage within spec.

Mostly the same computer and power supply.  Change MB few times but use back Power Supply which was not damaged. The PSU is expensive brand and provides sufficient voltage.

So what do you think about the different readings from the AVR and the Analyzer? I suspect the AVRs in the market are con job.

I tested another AVR (different brand in another room) which is also displaying the 230V in the LED display. But the Analyzer plugged in shows 244-245V.

Hi there, my unit LCD screen show no number and the backlight LCD keeps on flickering. Can I get exchange warranty?

Item(s): Watt/Volt Meter with Electricity/Power Consumption Calculator

Package includes: Multifunctional Wattmeter with english language manual in retail box.

Price : RM$87
Shipping & handling : $6 West Malaysia / $9 East Malaysia

Dealing method: Poslaju

Warranty: 1 year local warranty

Ever wonder which electrical appliance in your house is the most power hungry? Just plug it into the Multifunctional Wattmeter and you will know the answer in seconds. With these easy to use device, you no longer need to pay high electrical bills by identifying & eliminating those old & inefficient electrical appliances.

Kindly refer to this link for more usage examples : Watt Meter with TNB Bill Calculator,  Post #29



Features :
　　1. Measure supply voltage in real-time.
　　2. Measure appliances power usage in real-time (0~3000W)
　　3. Show accumulated power consumption (0~9999kWh)
　　4. Calculate the cost of energy according to the preset price of energy (0~$9999); price of energy can be preset to the local price by users.
　　　　Two ways for calculating power consumption and power cost: electricity consumption and electricity cost in single operation period and
　　　　accumulated electricity consumption and electricity cost in all operation periods; can be manually cleared to 0.
　　5. Operation condition monitor: The indicator light will flicker when the real-time ratio of operation condition reaches its alarm point.
　　　　Ratio of operation condition is the ratio between accumulated operation time per hour (running power is over preset standby power)
　　　　and 1 hour. Alarm point for ratio of operation condition and standby power can be preset.
　　6. Show the operation time of appliances (0~24h~9999d). Two ways for calculating operation time: time in single operation period and
　　　　accumulated time in all operation periods; can be manually cleared into 0.

Working conditions :
　　Voltage : 160~280V AC, 50Hz
　　Peak load : 15A
　　Temperature : -10~60°C
　　Humidity : 10~95% RH


Kindly refer to the topic below for other measuring equipments & accessories such as handy luggage weighting scale, battery tester, thermometer for human :
[WTS] Measuring Equipments & Accessories