You can try it with the hi-fi power cables but not speaker cables as those are not rated for such high voltage. But unless the entire system from the DB is of such, it will not make much of a difference

overall i agree ur method but correction abit if u dun mind, 200w is way to high for laptop. c2d only uses 35W max (<29W for penryn processor). solo core centrino about 25W max load. almost 15%of ur pc calc lol desktop also no need 300W so high myb less than 200W n take 50% for load.

pc 200W x 4 = 800 x 50% x 18 = 7.2 kwh
nb 35w x 2 = 70 x 18 = 1.26 kwh

lastime i rmb i on 24/7 my centrino nb dl calc max RM9 /mth only that is 100% load somemore lol

look like pcs very low consumption only lol

Bro, to make it simple, it's like this. Imagine 100 cars travelling from KL-Penang using the old narrow road. It might take 8 hours or more, waste of fuel due to low gear usage, overtaking at low speed, driving slow at high rpm when preparing for overtaking and more. Well these might increase the engine heat due to the unstable speed and many obstacles but if you take the PLUS highway which is much wider and less resistance, you will reach the destination perhaps within 5 hours with less obstacles, constant speed.

The story goes more or less the same with the cable. The thinner the cable, the less space for the electricity to flow. Due to the electric current travels and the speed of light perhaps, it needs proper wide cable to flow smoothly. The heat that you feel on the cable is the waste of energy due to thin cable. Electric energy converted to heat energy but you don't utilize the heat energy, so it's a waste. Due to the wastage of electric to heat energy that you don't utilize, the machine needs more energy from the DB to fullfil what it needs. If the cable is thick enough where there's less energy conversion happens before it reaches the machine, logically it saves your pocket.

ahahhaha.... u guys really creative. but the answer is NO. using bigger cable will not cause the power consumption lower... and the losses in the cable are not significant as well if one take out the cable manufacturer catalogue and study the cable resistivity... However, appropriate cable size selection shall required some calculation to determine it...

Hi, my electricity bill is high also. I feel the culprit is the air cond. Can you help me to work out the electricity cost for air cond. for 3 units at 1HP each for say 8 hours.

Thank you.

1 HP power air-con generally consumes about 20~30 cents per hour

I prove it with my own electricity bill.

Thanks for your explanation am_eniey. I understand the wire current flow capacity between small wire and thick wire. What I still don't understand is will a thicker wire have benefit if ordinary wire is enough for the appliance power? If in imaginery way, the highway already have extra 20-30% capicity to accomodate the car, build another few lane will make the car reach the destination faster?

What I can imagine is, the appliance using 10A current and the wire suppose to carry 10A current. Because of the wire small and high resistance, some current lost to the heat a long the wire and actually is supplying maybe 1A or 2A extra in order the appliance can get 10A. Is this what you mean?

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Added on July 31, 2009, 12:11 pmYour bill high problem is, maybe your aircon compressor running non stop due to under capacity. Buy the aircon HP according to your room size not your wallet size.

This post has been edited by ozak: Jul 31 2009, 12:11 PM

Thicker cable is always better. It's just the cost of the cable that matters to most people. It is indeed extra expensive. I spent around RM1K just for the cables only but long term wise, it benefits me.

There are multibillion of electrodes flowing in a cable. If a machines requires 10A, it still gets 10A from any type of cable. The difference is how the 10A is coming through from the DB to the machine, through a thin or a thick cable. Just like billions of cars travelling from KL-Penang at one time for example. Which type of road has lesser resistance, PLUS highway or the old road. KL is the DB, Penang is the machine. The road is the cable. It's not quite a comparison btw but at least it gives a better picture.

This post has been edited by am_eniey: Jul 31 2009, 12:18 PM

[COLOR=blue][COLOR=blue][quote=cherroy,Jul 31 2009, 10:04 AM]1 HP power air-con generally consumes about 20~30 cents per hour

[/quote]

Any formula to work out ? Please share

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Added on July 31, 2009, 7:00 pm

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Added on July 31, 2009, 12:11 pm
Your bill high problem is, maybe your aircon compressor running non stop due to under capacity. Buy the aircon HP according to your room size not your wallet size.

[/quote]

Is the thermostat setting affects the compressor running time? My room size is 22x14. What is optimum air cond HP?

Kindly teach the basic calculation.

This post has been edited by Calmman: Jul 31 2009, 07:00 PM

Compressor will be shut down when reaching preset temp by you. So if room is too big, it won't able to reach the temp preset ley day 24, so compressor will run non-stop.

I forget the exact figure, but roughly 1 HP is recommended around the size of 12x12, and 1.5HP is suit at around 18x18

I would say 1.5 HP is the optimum for your case.

Correct me if I am wrong.

over providing is good off course, but is not optimize... u can go around and ask those competent engineer and i doubt that you idea really save the power consumption. As i said before, the larger cable, the resistivity different are not really significant... Best is to select your house hold equipment properly... for eg selecting an inverter a/c or fridge... as inverter motor will not cause too many start stop which draw huge current... inverter motor varies the speed to maintain or to cool down the temperature...

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Added on August 1, 2009, 12:16 amyes, u r right! undersizing a/c will cause that... basically ur room required 1.5hp.... if ur room is facing east/west then u might need to consider 2hp... basic formula to sizing a/c is to determine the BTU required.... which is proportion to area.




This post has been edited by gunh: Aug 1 2009, 12:16 AM

Thank you Cherroy & Gunh for sharing. BTW, what is BTU? I often heard of this BTU when talking abt air cond. Dont mind enlighten on this.

Lately I am surveying on ways to get rid of the stifling heat inside the house when come home and reducing electricity cost. Another THREAD in this form on ROOF INSULATOR & SECURITY also relate to what we discuss here.

I have visited the site www.tclmalaysia.com abt cellulose insulation from USA and is considering to install it.

Seems like working well

Any advice???

BTU = British Thermal Unit..

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Added on August 1, 2009, 1:29 pmTo futher support my previous statement... i've manage to get some technical information from Draka Cable.

For 1.5mm sq cable, the conductor resistance is 12.1 ohm for every 1 kilometer / 1000mtr
For 2.5mm sq cable, the conductor resistance is 7.41 ohm for every 1 kilometer / 1000mtr
For 4.0mm sq cable, the conductor resistance is 4.6 ohm for every 1 kilometer / 1000mtr

so by upgrading say 2.5mm sq cable to 4.0mm sq cable, the resistance different is 2.81 ohm for every 1000 mtr or 0.00281 ohm per meter.
and for an average power point in house, the distance are or about 15meter, which work out to be 0.04215 ohm.

u think such small significant can play role in power consumption? And, when u upgrading the cable, u will need to use a bigger cable conduit or casing... which is also cost. However, no doubt each cable be it 1.5, 2.5 or 4.0mm have their own current capacity limitation... and as long the electrical engineer done his calculation + some safety factor, then it should be alright.

Just like ur house Syabas incoming pipe.... dont tell me if u pipe ur whole house to bigger pipe to all ur kitchen or toilet, then ur water bill is less? does not make sense right?

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Added on August 1, 2009, 1:42 pmTo futher support my previous statement... i've manage to get some technical information from Draka Cable.

For 1.5mm sq cable, the conductor resistance is 12.1 ohm for every 1 kilometer / 1000mtr
For 2.5mm sq cable, the conductor resistance is 7.41 ohm for every 1 kilometer / 1000mtr
For 4.0mm sq cable, the conductor resistance is 4.6 ohm for every 1 kilometer / 1000mtr

so by upgrading say 2.5mm sq cable to 4.0mm sq cable, the resistance different is 2.81 ohm for every 1000 mtr or 0.00281 ohm per meter.
and for an average power point in house, the distance are or about 15meter, which work out to be 0.04215 ohm.

u think such small significant can play role in power consumption? And, when u upgrading the cable, u will need to use a bigger cable conduit or casing... which is also cost. However, no doubt each cable be it 1.5, 2.5 or 4.0mm have their own current capacity limitation... and as long the electrical engineer done his calculation + some safety factor, then it should be alright.

Just like ur house Syabas incoming pipe.... dont tell me if u pipe ur whole house to bigger pipe to all ur kitchen or toilet, then ur water bill is less? does not make sense right?





This post has been edited by gunh: Aug 1 2009, 01:42 PM

I would think if one is using near the capacity of the cable, by using larger cable, will cause less heat and saving on some resistance as well as bigger size cable having less resistance in the first place. But whether the saving is significant or not, still a lot can be studied and explored.

As for ordinary household the saving a few cents might not able to recoup back what had invested in bigger cable. Just like inverter air-con will save electricity. But if you are using just a few hour per day, the amount of power bill saved might not able to recoup back the extra money fork out to purchase a inverter air-con compared to ordinary one.

Inverter air-cond save electricity but it depends how it is being used. If not the extra money fork out is not worthwhile. If your compressor need to run 100% all the time (under sized), inverter air-con won't able to save you a single cent.

The saving power bill changing from smaller to bigger size cable as stated by forumer could be the previously old smaller cable had crack or deteoriated due to whatever reason in the first place, so by changing the new and bigger cable lead to power bill save.
Just my wild guess.

Electricity flow is not the same as water flow. You can elaborate this as I can see that you know better.

cherroy, perhaps the cable u mentioned are already under size at the 1st place... if the cable being selected is appropriate... it will not cause cable crack... unless the wire has been there for more than 20yrs... Engineer always perform their duty to make sure the right choice being made based on technical... from civil, electrical & mechanical engineer... Cable selection shall also consider the derating factor which is determine by type of cable and method of installation... Yes, if selection or choice is wrong, then the cable will generate heat, due to voltage drop issue as well...

I alway set at 25deg and put everything in auto. My experience is my first aircon 1HP average bill around RM100+. Than change to inverter type 1.5hp. Now bill average RM65+.

A little sidetrack - has anyone had issues with their inverters (spoilt, destroyed in power surge, etc). The inverter circuits has electronics and wonder how they stand the test of time against AC circuits.

I know one of my inverter got spoilt before (not an aircond inverter) but a florescent light inverter. It was an el-cheapo, but any electronics will be sensitive to AC currents, depending on the circuit protection. So I was kind of cautious in choosing inverter AC fearing it could result in the same problem as my florescent inverter.

Those who used airconds with inverter > 4 years running (finish pay back period), care to comment?

Err.... flourescent light got use inverter? Sorry noob in this area.

What the use of inverter in flourescent then?

As far as I knew, inverter is some device that control the current flow once the motor doesn't need so much power. So how this applied on flourescent?