Help on Power conditioner

In my house the Power having a fluctuation and found voltage variation between day and night times. Here the voltage 230v and day time we are getting 210v and night time 220-230v.

I have pass lab xa.5 mono blocks hence I am worried about the safety. So, You all suggest me the best stabilizer or conditioner with surge production to buy.

One of my friend has informed me that Pass is not recommended any power stabilizer, conditioner or re generators. Is it correct ?

Any one using these kind of accessories for Pass lab products? How the performance
of the amps using these accessories?

I am expecting suggestions and advise from you all.

Thanks in advance.
If your power is fluctuating a power conditioner will not help, you will need an AC regenerator like PS Audio Powerplant P-3, or P-5, or P-10. I have the P-3 and it did wonders for my system. I think most amp manufacturers do not recommend conditioners because they are current limiting. Most modern AC regenerators are not current limiting.
I experienced the same problem at my home. I borrowed a balanced power supply from a friend built from a kit from Transcendent Sound. It was incredible the improvement was immiedate. At the time, I was running two Classe CA-150's in mono. I never ran out of power and connected my front end which quieted everything down. I bought the kit and love the unit. You can buy the unit built. I have friends with the aforementioned PS equipment and I am not the least bit envious. Saved a lot of money,too. Hope this helps. Steve
Rabbani, if I were you I would give the local power company a ring, and have them investigate your problem. 210V is below the UK and Australia mains voltage tolerance standard of +10%/-6% of 230V (253V-216.2V).

Is the daytime low always 210V year round? During the warmer months of the year, when more air conditioners are in use, it is not uncommon for voltage to fall a little below minimum tolerance due to the increased load on the system. The utility companies will also deliberately lower the voltage to reduce strain on the power grid, and prevent blackouts.

Yes Mr.Glen. The day time always 210v and summer time its go 180-190v. But, Night time we get 220v and summer time its go to 200v. Secondly, How I can control the fluctuation?
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All equipment designed to placed on European market since 1995 has to operate at 230V +/-10%. 180-190V is low but it should not damage anything. Why would you like to control fluctuations? Does it affect the sound?
No Kijanki, only am worried about saftey. Becoz sending for repair the unit to manufacturer is a new amp cost for me.
Rabbani, it sounds like you have undervoltage problem. It should not destroy anything. If it doesn't affect the sound leave it alone. Still, voltage spike caused by lightning or nearby inductive loads (like motors) switching is always possible. I use Furman Elite 20PFI that has strong non-sacrificial over/undervoltage protection. It provides high peak current by employing big capacitor and big inductor that store energy. I cannot hear any difference in dynamics with my power amp. It also have separate outlet banks for low current audio and also for video. Those banks have strong filters that clean all the junk from the power line before it enters my system.
Rabbani, I had the same issues as you. Where I live in E london is semi industrial with motors and transformers in nearby plant, cellphone aerials and internet booster stations, and broadband on c24/7 in every apartment around me.
When I ran my Burmester conditioner, the realtime voltage readout never showed the correct 230v, no, it fluctuated btwn 210v-250v ie +/-15%, moment to moment. From what I gather the psus of delicate audio equipment can't cope with such swings.
When I decided to move to 4kVA balanced power I scrapped the Burmester, but for fun put it in series after the new transformer. The realtime voltage now never fluctuated more than 227v-233v ie +/-1.5%, and the system REALLY benefits. Balanced plus conditioner sounds no good, so getting rid of the conditioner totally, and relying on balanced is where I am at present.
It has been a total revelation, the improvements wrought by the Burmester maintained ie delicacy and detail, but with none of the disadvantages ie softened dynamics.
I'm using a cheap, industrial grade, non audiophile 4kVA unit sourced in Essex, England called Airlink, at 10% of the cost of my Burmester.