How to ensure AC installation is correct?

[avi]

Both the appliances are installed improperly. AC installation is much more complex. You should take charge here instead of relying on technicians.

So how did you correct them? Is it possible to correct them once installed?

btw I found another piece of manual and this one has some instructions. I will read through each of them and understand. Following is the indoor unit section:

Minimum they suggest is 4sqmm (mine is 2T Ac).

What does following mean:

The distribution has to be of an low impedance, normally required impedance reaches at a 32A fusing point

And also

No other equipment has to be connected with this power line

Is this a hard warning? or is it okay to add other equipments?

This is how the current arrangement in home:

Electricity board two wires -> Meter -> two wires go to Inverter (via fuse), two separate wires which powers Fridge and Geyser

This was done so that Fridge and Geyser run without inverter and rest of the full home on inverter.

Currently the wire for Fridge and Geyser are of 2.5sqmm wire.

So I was thinking to get this whole wire replaced by 4sqmm and run via the rooms where geyser and fridge are and finally connect them to AC.

We don't really have any distribution board. The arrangement is simple, electricity board to meter, meter to entire home.

What shall I do?

 

[bigbyte]

The cable has some resistance and capacitance, the vector sum of both is called impedance. Use a good quality 4sq mm multistrand cable( 3 x 1 core or 3 core ) and you will be fine unless the length is very high. Don't use older type 3/20 or 7/20 cable.
Make sure that cable from meter is coming directly to your AC distribution box. Don't touch Fridge and Geyser wiring.

 

[avi]

The cable has some resistance and capacitance, the vector sum of both is called impedance. Use a good quality 4sq mm multistrand cable( 3 x 1 core or 3 core )

Yes, I got a multistranded one and its not 3/20 or 7/20.

and you will be fine unless the length is very high.

So earlier plan was to move the 4sqmm wire around the home so that geyser and fridge also would be applied. For that I needed 100meter wire (x 3) since it has to go via other rooms

now, if I want to connect to meter directly, the distance will be small. Probably 25 meter (x 3)

Make sure that cable from meter is coming directly to your AC distribution box. Don't touch Fridge and Geyser wiring.

There is no distribution box in home, as I said earlier:

Electricity board two wires -> Meter -> two wires go to Inverter (via fuse), two separate wires which powers Fridge and Geyser

now I need to take out two more separate wires from Meter to Ac?

 

[bigbyte]

Make sure that cable from meter is coming directly to your AC distribution box

There is no distribution box in home, as I said earlier:

By "AC distribution box", I meant the Havells Box that you have purchased. So run three multistrand Wires 4 sq mm each ( or one 3 core 4 sqmm Cable) from meter to your Havells AC box.

 

[avi]

By "AC distribution box", I meant the Havells Box that you have purchased. So run three multistrand Wires 4 sq mm each ( or one 3 core 4 sqmm Cable) from meter to your Havells AC box.

So is it okay there are 3 pairs of wires coming out of meter?

- one pair to inverter
- one pair to geyser + fridge
- one pair to AC

Since I shouldn't add any other equipments to AC wire.

 

[Criminal]

So how did you correct them? Is it possible to correct them once installed?

It's not possible to fix the built-in hob, without replacing the whole granite counter-top. Chimney, can still be done but not without dismantling the hob beneath... which means, kitchen is not usable for sometime. What I wanted to highlight was that blindly relying on company installers is foolish.

Is this a hard warning? or is it okay to add other equipments?
...
So I was thinking to get this whole wire replaced by 4sqmm and run via the rooms where geyser and fridge are and finally connect them to AC.

You can add geyser to your AC line as I assume you would run these two appliances exclusive of each other. Fridge has to be on a separate line from AC as it'll increase the load on the wire but a 4mm cable can take this load pretty easily.

Impedance thing is already explained by bigbyte. 4mm can handle 32A load. And as you are planning to have a direct connection with meter, you will never cross this limit.

So is it okay there are 3 pairs of wires coming out of meter?

It's okay. If it's your own house, get a distribution box installed.

 

[bigbyte]

So is it okay there are 3 pairs of wires coming out of meter?

It's okay. If it's your own house, get a distribution box installed.

As he said. Plus don't forget the earthing.

 

[avi]

As he said. Plus don't forget the earthing.

Checked earthing today, working fine. No issues.

You can add geyser to your AC line as I assume you would run these two appliances exclusive of each other. Fridge has to be on a separate line from AC as it'll increase the load on the wire but a 4mm cable can take this load pretty easily.

Since fridge will be on always, I guess I have to use separate line.

It's okay. If it's your own house, get a distribution box installed.

Can I get plug-and-play boxes? For example, something like this - http://www.snapdeal.com/product/havells-4-way-spn-qve/116818979 I mean, just get this and fit, no need of adding anything extra. If yes, can you guys recommend me one which comes with everything? 4-way is fine (assuming 1-inverter, 1-geyser+fridge, 1-AC and 1-extra)

problem is my electrician doesn't know about distribution boxes, but he can do if I instruct him how to.

 

[bigbyte]

The DB will come with Din rails and Bus bars only. You have to mount MCB's as per your requirement.
Better to buy one that has provision to install ELCB/RCCB as well. Go to your neighbourhood electric shop to check what suits you best, he may be able to suggest as well. Somethings are better not bought online.

 

[avi]

^I will buy offline itself, but even local electrical shop guy also doesn't know much.

so get DB Box, install MCB, ELCB, RCCB. Right?

 

[bigbyte]

It's ELCB or RCCB, better to install RCCB. ELCB are anyway hard to get these days and have beem replaced by RCCB.
Connection will be
1. Meter to RCCB. 4 or 6 sq mm Wires, Live neutral Pair and Earthing
2. RCCB to Bus Bar.
From Bus bar to
3a. 10A / 16A MCB for Inverter ---> 2.5 sq mm existing Wire Pair + Earthing
3b. 10A / 16A MCB for Geyser ---> 2.5 sq mm existing wire pair + earthing
3c. 16A/ 20A MCB for AC --------> 4 sq mm new Wire Pair + Earthing
3d. Anyother MCB as spare.

 

[singenaadam]

ELCB is tricky. Recommended rating is 30 mA. However even with smallest defective wiring it will trip. Make sure your wiring is 100% OK before going for ELCB installation. Even switching on/off of appliances like ACs can sometimes trigger trips. Get the wiring checked out before actually buying an ELCB.

 

[Criminal]

Can I get plug-and-play boxes? For example, something like this - http://www.snapdeal.com/product/havells-4-way-spn-qve/116818979 I mean, just get this and fit, no need of adding anything extra.

If this 4-way distribution board can accommodate only 4 MCBs then it's not enough for your current setup. The MCBs you are going to buy (as mentioned by bigbyte) are Single Pole only (SP MCB). They take only "live" wire, which is alright, but you also need a Dual Pole MCB, which accommodates neutral as well. This DP-MCB will also act as a master MCB and rest of the MCBs/RCCB would feed off from it. DP-MCB will be of min 63A. Rest of the SP-MCBs - as specified by bigbyte.

If you are planning to install anything to tackle "residual current" then make sure your distribution box has space for it. DP-MCB and RCCB (and the likes) are bigger than normal MCBs.

MCBs will help in avoiding fires due to short-circuits. Right now, you don't have any kind of fuse to tackle over-load... which means instant fire/meltdown in case of short-circuits.

MCB won't protect you from shocks and an RCCB can help. But a good earthing is equally fine measure - but not reliable.

And yes, distribution board installation is pretty much plug-n-play. Even you can install it.

Meter ----{6mm wire}---> DP-MCB --> RCCB (optional) ----{thru bus bar}---> Individual SP-MCBs

 

[avi]

^thanks for the replies! Posting from mobile so not able to quote.

I went to local electrical shop today and this guy has no idea about RCBB or distribution box.

I will visit another one in the nearest town (the guy who sold me 32A MCB for AC Box) and get all the parts. I will have it fixed by my electrician.

I will get all the specified parts mentioned by @bigbyte.

Right now I do have fuses in home, but these are old kinds. Like with made of ceramic and have a copper wire inside. These come after meter and before inverter (however fridge and geyser have no fuse).

No issues with earthing either, checked today myself and also by electrican.

Could you guys also tell me specificafion for RCBB and DP MCB?

And also wouldn't 16A MCB trip if it's used for AC? (Like I was suggested of 20A here - https://www.techenclave.com/communi...allation-is-correct.179278/page-2#post-208092)

Or is the arrangement is my AC box has 20A MCB and 16A in distribution?[DOUBLEPOST=1461956618][/DOUBLEPOST]

ELCB is tricky. Recommended rating is 30 mA. However even with smallest defective wiring it will trip. Make sure your wiring is 100% OK before going for ELCB installation. Even switching on/off of appliances like ACs can sometimes trigger trips. Get the wiring checked out before actually buying an ELCB.

Thanks for the tip! But I am buying RCBB[DOUBLEPOST=1461956686][/DOUBLEPOST]Also, my first priority is to get the AC installation done quickly. So right now all 3 pairs of wires will be connected to meter directly. Monday I will have AC installed and Distribution Box by Tuesday/Wednesday (or may 1-2 days more). But parts I will be getting tomo only since I have to travel to diff city.

 

[Criminal]

I hope this post isn't too late and you haven't bought the items already.

Could you guys also tell me specificafion for RCBB and DP MCB?

RCCB: Although I have it, I couldn't put it to use because of bad earthing at my place. Someone who already has it installed can answer. Or ask the guys at your electricity board.

DP-MCB: This should be equal to the rating of the fuses that you already have... because someone (your electrician) must've done the load calculation for your house. Obviously, DP-MCB would also be equal to the sum of all of the child SP-MCBs. But I don't have any references to prove this point.

You must've added few more appliances to your house after the fuses were first installed. So, you need to re-calculate the power requirement for your house to make sure the MCBs are of correct rating. Add up the wattage of each device on the three separate power lines you are planning to have, and divide that by 230. This is the total load in amperes for each line. And the MCB rating is 25% more of the load in amperes. i.e., MCB amps = Load Amps + (Load amps X 0.25)

You'll need to go for the MCB of next higher rating if the one with your exact requirements isn't available. e.g., if your calculations demand 9A MCB then get the 10A.

Now all these regular MCBs are of "B Type", which are meant for resistive load. People don't go into such details but ideally, you should get a "C type" MCB for inductive load. Anything with compressor is classified as inductive load, and so are the water motors.

Your AC and fridge come under inductive load category but if possible, get a C type MCB for your AC. Geyser is resistive.

And also wouldn't 16A MCB trip if it's used for AC? (Like I was suggested of 20A here -

Since, the starting and running amps aren't available for your AC model, I can't give you a number with 100% confidence. But if you take example from what people generally do with their 2T AC, then it's the 20A MCB. Type C, if you are too finicky. And you just need one MCB. You've got Havells box which has a provision for MCB, so you don't need to install one at the distribution box.

 

[avi]

I hope this post isn't too late and you haven't bought the items already.

Nope, something came up and I couldn't travel. I will be buying them by tomo evening.

RCCB: Although I have it, I couldn't put it to use because of bad earthing at my place. Someone who already has it installed can answer. Or ask the guys at your electricity board.

man people at electricity board have no idea. they are helpful, but they don't know. I will ask the shop keeper himself and take a decision.

DP-MCB: This should be equal to the rating of the fuses that you already have... because someone (your electrician) must've done the load calculation for your house. Obviously, DP-MCB would also be equal to the sum of all of the child SP-MCBs. But I don't have any references to prove this point.

I see. Load is not calculated, but I can do it myself. Not many heavy electronics in home though.

You must've added few more appliances to your house after the fuses were first installed. So, you need to re-calculate the power requirement for your house to make sure the MCBs are of correct rating. Add up the wattage of each device on the three separate power lines you are planning to have, and divide that by 230. This is the total load in amperes for each line. And the MCB rating is 25% more of the load in amperes. i.e., MCB amps = Load Amps + (Load amps X 0.25)

I will do this. Btw with this formula, for AC it comes around 10A, but I think it's because it doesn't include initial high amps required by AC.

Now all these regular MCBs are of "B Type", which are meant for resistive load. People don't go into such details but ideally, you should get a "C type" MCB for inductive load. Anything with compressor is classified as inductive load, and so are the water motors.

Your AC and fridge come under inductive load category but if possible, get a C type MCB for your AC. Geyser is resistive.

I will keep this in mind. I will get a C Type MCB for AC and B Type for Geyser + Fridge

Since, the starting and running amps aren't available for your AC model, I can't give you a number with 100% confidence. But if you take example from what people generally do with their 2T AC, then it's the 20A MCB. Type C, if you are too finicky. And you just need one MCB. You've got Havells box which has a provision for MCB, so you don't need to install one at the distribution box.

So I will go with a single 20A, C Type, MCB for AC, which will be installed in Havells box.

So list of things to get so far:

- RCCB (will go with as suggested by shop guy) - RCCB also have types, so for me Type AC should be fine
- DP MCB (will go with as suggested by shop guy)
- 4 way distribution box (SP & N)
- 20A C Type MCB (will be exchanged with 32A one I have)
- 2 10A B Type for Inverter and Geyser (I will calculate power requirements and decide on it)

I just noticed that my stabilizer's amp rating is 15A, this is getting tricky now.

 

[Criminal]

- 4 way distribution box (SP & N)

just make sure it has enough space for all the MCBs, RCCB + spare room

I just noticed that my stabilizer's amp rating is 15A, this is getting tricky now.

If you could get the starting and running Amps requirements for your AC then everything would be crystal clear. There has to be 2 power or amp ratings for any compressor based device, no matter what people say. You calculate the rating of MCBs/Fuses based on the full load (the higher value of the two).

 

[avi]

If you could get the starting and running Amps requirements for your AC then everything would be crystal clear. There has to be 2 power or amp ratings for any compressor based device, no matter what people say. You calculate the rating of MCBs/Fuses based on the full load (the higher value of the two).

I called Carrier care and even they don't have any idea. W T F