Author Topic: Fluctuating house voltage  (Read 764 times)

Offline Johnnie F.

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Fluctuating house voltage
« on: February 01, 2019, 07:18:28 PM »
Quote from: ken kenobie on k-f
I don’t know if its just where I live out in the bush , but recently the mains voltage to the house seems to be fluctuating all the time.

Any one else suffering the same annoying house voltage problem

It's a huge problem almost anywhere out in the sticks; it will be felt especially in the summer months from March to June, when many people operate their air conditioners. Worst it is from around 7 to 9 p.m., when people come home from work and start their rice cookers. Then the voltage drops in some places even below 140V. At that voltage your air conditioner will eat full electricity but not cool at all, your fans might get stuck and the motors burn through etc.

There are AVR (automatic voltage regulator) available. but alas, if you don't plan carefully and get what you actually need, you might end up with even more problems than before. It needs to have sufficient power for your needs, or it might shut off all at voltage too low, and your fridge is without power until you notice the problem and switch manually. Only some automatically switch to "bypass" then.

Best are those with "pump" function, not just bypass, in case they cannot manage the step-up transformation. Those automatically switch to operation with capacitors instead of transformers, when the transformer cannot handle it anymore due to too much draft and too little input. They will eat a lot more kW, but keep things working.

I use a Voltage Step-Up Transformer I can adjust manually, and after that a medium size AVR, cost together about 30,000 THB. Makes up to  3 air cons and water heaters etc. still work fine, when much of Thailand suffers from too low voltage to cool down.



If I started from the beginning, I would buy this (only, instead of strong voltage step-up transformer and medium size AVR):

https://www.lazada.co.th/products/cbc-automatic-voltage-stabilizer-20kva-i165812169-s202888502.html

If you're already having problems, don't buy one of those cheaper AVRs. Good ones suitable to help air cons etc. cost 25,000 THB up. And don't expect them to lower your electricity bill. But they help to get what you pay for in any case!



Online Taman Tun

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Re: Fluctuating house voltage
« Reply #1 on: February 01, 2019, 07:50:58 PM »
Hi Johnnie, that transformer is pretty good for high power items, but maybe consider a UPS for more delicate items like computers:- This one has input range from 140-300 V and gives good stable output. I hope you have KF running on one of these!


Product details UPS APC BX800LI-MS 2 year warranty by INGRAM, SYNNEX, SIS
Output power capacity 415Watts / 800VA
Max Configurable Power (Watts) 415Watts / 800VA
Nominal Output Voltage 230V
Output Frequency 50/60 Hz +/- 1 Hz
Output Frequency 50/60 Hz +/- 1 Hz
Topology Line Interactive
Waveform type Stepped approximation to a sinewave
Output Connections (1) IEC 320 C13 (Battery Backup)
Transfer Time 4ms typical: 6ms maximum
Nominal Input Voltage 230V
Input frequency 50/60 Hz +/- 3 Hz (auto sensing)
Input Connections IEC-320 C14, NEMA 5-15P
Cord Length 1.22meters
Input voltage range for main operations 140 - 300V
Number of Power Cords 1
Type of Input Protection Required 3-pole breaker
Maximum Input Current 7.0A
Input Power Factor at Full Load 0.52
Batteries & Runtime
Battery type maintenance-free sealed Lead-Acid battery with suspended electrolyte: leakproof
Included Battery Modules 1
Typical recharge time 6hour (s)
Replacement Battery APCRBC110
Expected Battery Life (years) 2 - 4
Runtime View Runtime GraphView Runtime Chart
Efficiency View Efficiency Graph
Communications & Management
Control panel LED status with load and battery bar-graphs and On Line: On Battery: Replace Battery: and Overload Indicators
Audible Alarm Alarm on battery: distinctive low battery alarm: overload continuous tone alarm
Surge Protection and Filtering
Surge energy rating 273Joules
Physical
Maximum Height 200mm, 20.0CM
Maximum Width 115mm, 11.5CM
Maximum Depth 256mm, 25.6CM
Net Weight 6.5KG
Shipping weight 6.7KG
Shipping Height 290mm, 29.0CM
Shipping Width 205mm, 20.5CM
Shipping Depth 345mm, 34.5CM
Color Black
Environmental
Operating Temperature 0 - 40 ° C
Operating Relative Humidity 0 - 95%
Operating Elevation 0-3000meters
Storage Temperature -15 - 40 ° C
Storage Relative Humidity 0 - 95%
Storage Elevation 0-9000meters
Audible noise at 1 meter from surface of unit 45.0dBA
Conformance
Approvals CE, WEEE
Standard warranty 2 years repair or replace
Sustainable Offer Status
RoHS Compliant
REACH REACH: Contains No SVHCs
If the old only could, if the young only knew.

Offline Johnnie F.

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Re: Fluctuating house voltage
« Reply #2 on: February 01, 2019, 08:24:16 PM »
No, TT, for my computer, Stereo etc. I use a UPS Power Inverter and an 80 Ah pickup battery, already as preparation for a planned solar power system. Works a 1,000% better than those UPS they sell for computers. The voltage is kept steady for all appliances in the house by the step-up transformer and the AVR already. But blackouts are also something we suffer from.

 



Thailand