Help from Italy

[sampei]

Hi everybody.
I am here asking for your help as I am not able to come up with a solution.
My system is done this way: I have the main house power coming from the counter that goes into this stabilizer SINGLE PHASE ELECTRONIC VOLTAGE STABILISER SED range 5kw with a standard power supply contract of 3kw.
than I have the stabilized output supplying the main house and a fridge+dry machine in the garage.
As the counter is at the bottom of the building, I have a 6mm2 wire going from the counter to the stabilizer and than back up to the main house as stated with the italian law. I am therefore excluding a wire issue.
without the stabilizer, I have a volt value around 240 and I am experiencing some noises with the main appliances in the house included the tv or stereo amplifier that came very noisy. for this reason I installed this stabilizer that will give me a 230 +-2% volt current and here comes the problem.
I have a apc ups device that protects the pc and the NAS and it clicked only when the condominial elevator starts (without the stabilizer) but since I installed the stabilizer, I have it clicking more often even when the A are 0,30 and the fridge starts or other appliances start.
Yesterday I had the dry machine working in the garage and with the control device I am using at home (http://www.imeitaly.com/docs/NT752.pdf just for the value shown and not for the power relay function) I saw that when the dry machine powers from time to time, the V are usually 226-7 while when it stops they go back to 233-4 with a load on the stabilizer of 23-24% meaning 1 1,2kw.
I know there are a lot of info missing (which I'll be pleased to add if needed) but I was wondering what's wrong with my system as it seems that with the stabilizer on, I am having more clicking and problem than before. when the fridge starts, the ups is clicking and the same is still happening when the elevator starts.
I am wondering if the stabilizer works or not. moreover I am expecting the V drop with a high A usage, while the fridge or led lights make the A increase only few decimals but I am experiencing a V drop that cause the light to flick. moreover if this happens with a small A change, I am scared to see what will happens when air condition or oven starts.
thanks for your patience and any useful advice.
Valerio

 

[Marvo]

With these kinds of problems I would start with the basics.

I would check all terminations in your main house electrical box. Poor connections or terminations can cause large voltage fluctuations when a load such as a motor is connected.

If undersized wiring has been used somewhere in the installation similar problems could occur.

I would also check the earthing system is good and up to scratch.

To be honest there many possible causes to the problems you describe. If it's not something obvious you will need to find someone with the testing equipment and the knowledge how to use it. With the right equipment and experience the problem shouldn't be too difficult to find and repair.

 

[sampei]

thanks for the reply and even if it will take time, I'll check all the connection especially those behind the main appliances. for the cables, the italian law sets a minimum of 6mm2 and it's what I have from the counter to the main box in the house. from there, there are the standard 1,5mm2 or 2,5mm2 depending from the usage. 1,5mm2 for lights and 2,5 for all the rest.
the house is 5 years old and the ground should be measured but I think it's fine.
My main concern is that all disappears if I use the by-pass in the stabilizer and get a higher V in the house. if the by-pass is on, I get only the clicking from the elevator that has inverter in (all the light of the entire building dimmer when it starts) while this problem increase with the stabilizer and it's kind weird as it was supposed to solve all these matters.
thanks so far.
Valerio

 

[Marvo]

thanks for the reply and even if it will take time, I'll check all the connection especially those behind the main appliances.

It's most likely to be a problem with the connections in the main electrical box or even the main supply cable coming into the building.

the italian law sets a minimum of 6mm2 and it's what I have from the counter

I'm not understanding the word 'counter'. Can you give a description please?

 

[Knobhead]

To be honest it sounds like you have a problem with the supply from the utility. If the lift is on an inverter to start and it still dips the supply, the supply just isn’t up to the job.

Voltage drop will cause the voltage regulator to switch to by pass, but this takes time.

With the lowered incoming voltage combined with the lowered output of the voltage regulator your UPS is probably detecting mains failure.

I would also look for a way to remove the dryer from the regulated supply. With a dryer it serves no useful purpose.

 

[sampei]

the counter (actually is a really bad translation i guess..) is the device that is installed by the power company in order to get your consumptions. I guess the right translation is power meter. sorry for my english.
as I am writing, I'll try to give more updates:
I am expecting a V drop if there is a high A usage, right? while here in my house the V drop happens even when the fridge or the toaster starts. the V drops to 225-26 (please consider that we usually have 240 input value stabilized at 230 +/-2%) and goes back to 230-33V when the appliance stops. sometimes (I saw it now while typing) the fridge started and the V were 233 stable but the UPS clicked. silly question: can it be the UPS damaged?? with the previous one it never happened. I am not using this model APC Smart-UPS 1000VA LCD 230V
For example now I am reading a 228V with a 1,2A usage. is it normal? as I am not a technician, I was expecting to have 230 almost stable with a stabilizer on the line.
The stabilizer is perfectly working as when I installed it the first time and saw these problems, I returned it to re check if everything was fine and they said it was perfect.
The house is almost new and from what I can see, the original constructor dimensioned the wire as the law said, so we have 6mm2 from the basement to the house and I guess the same size is used for the elevator that has always given problem of light drop when you call it or when the fluid pump lifts the box. Unfortunately I am not able to see which is the dimension that comes into the whole building and it's probably a power company's fault as they are not able to deliver the proper power to come up with 12 families and the general facilities like elevator, centralized heating, automated gate and few other stuff.
on the manual of the stabilizer, it talks about a 16mm2 for input (from the power meter to the stabilizer) and a 10mm2 from the output, but I've been told they are too big compared to the 3KW I have as standard power contract. So we used 6mm2 for all the way as it was originally. when we installed it I had the chance to see how the electrical connections are made and trust me, I really got scared for how tiny they are.
What I am not able to understand is why I am not experiencing these problem when the bypass is on and the situation is the same as before. probably it is due to the 240V that even when there is a drop due to A increase, there is no light dimmer because the V is still above 230. correct?
I really don't know who to ask because my main installer as no clue at all. if you can please help me point towards the right direction, we can see where to investigate deeper.

 

[sampei]

I would also look for a way to remove the dryer from the regulated supply. With a dryer it serves no useful purpose.

thanks for the reply.
I have the chance quite easily to remove the dryer and a fridge from the stabilized line. do you suggest me to do it? isn't it worthy to have it stabilized?
the appliaces are these:
AEG LAVAMAT 76850A Lavamat 76850A - Washing Machines | Icecat.biz
Liebherr Gefrierschrank GP 1466 Premium (Auslaufmodell) Haushalt - Kühlen & Gefrieren - Gefrierschränke - Stand-Gefrierschränke - Mediaran
thanks a lot

 

[Knobhead]

A stabilised supply to the waster/dryer serves no purpose what so ever. So if it’s easy to do take them from the raw supply.

 

[lincoln]

Where are you in Italy, I will be back there in June around the Castelli region in Albano and have some test equipment there already. As stated by Tony main problems in Italy and Spain are that REC's do not like giving you a supply much over 6Kw this coupled to long runs of undersized tails result in horrendous voltage drop,

Lincoln

 

[sampei]

I live close to Milan, 25km into Turin direction.
Few updates:
I removed the dryer and the fridge from the stabilized line and the V are fluctuating between 226 and 234 as stated in the operational range of the stabilizer.
I also reduced the sensibility of the UPS and now it's clipping maybe couple times a day so I am moving in the right direction.
I still see light dropping when the main fridge in the house starts, but it's not always associated with a drop in V. I am thinking the fridge is leaving me....
Valerio