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Maximum distance between poles?


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1 hour ago, Sakeopete said:

The 3 bedrooms and Multipurpose Room will have 12 000 BTU AC Inverter Type.

IMO, those rooms wouldn't need more than 9-11K BTU and the "inverter" would be running at 1/2 of that most of the time anyway.

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1 hour ago, sometimewoodworker said:

The meter you should ask for rather depends on the final supply you want as if you are going to use a 30/100 supply then a temporary meter that size will not need to be changed when you on to the permanent tariff.

I just asked my wife about this, she replied that PEA told her they only have 15 amp temp meters available ATM  but if we want the 30 amp we can get that for the residential meter when construction is done.

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6 minutes ago, bankruatsteve said:

IMO, those rooms wouldn't need more than 9-11K BTU and the "inverter" would be running at 1/2 of that most of the time anyway.

There are several BTU calculators online that I tried. Some gave me a figure of 7k BTU others said 14k BTU. They ask the same parameters, very strange.

The price is not very different between a 9 k and 12 k BTU. Will the larger 12K use more energy or just cool faster? Thinking on the lines of burning calories, walking 5 kms and running 5 kms burns the same amount of calories, running just gets you there faster (and cardio).

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39 minutes ago, Sakeopete said:

We have a 4000 watt unit now and it get very hot if the tap isn't opened all the way. Otherwise my kids will stay in the shower until the storage tank runs dry.

Storage tank heaters are very different as they have plenty of time to heat the water,  however instant heaters have to be significantly bigger to get the same temperature but use less power overall as while it maybe double the posits used for much less than half the time.

 

So you can’t compare the 2.

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Here we go with a VERY quick and dirty load calculation.

 

Assume A/C load 3 x 12000 BTU at once (or possibly 2 x 18000 BTU in the lounge) = 18A

Assume 2 x 4500W water heaters at once = 40A (short time load - I'm assuming on-demand heaters).

 

So with all the little loads we're looking at peak loading of 60A ish.

 

30/100 meter would be very fine if available, in reality a 15/45 (with a 50A incoming breaker) would also be fine.

 

No need for 3-phase at this time even if you can only get a 15/45 (swap the incomer for 63A once inspection passed).

 

 

Your cable from the street to the house needs to be 16mm2 copper or 25mm2 aluminium for a 15/45 or 50mm2 copper or 70mm2 aluminium for the 30/100 to avoid volt-drop issues. The larger cables likely won't fit the meter or distribution board so your sparks will need to splice 16mm2 pigtails on to each end.

 

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3 minutes ago, Sakeopete said:

There are several BTU calculators online that I tried. Some gave me a figure of 7k BTU others said 14k BTU. They ask the same parameters, very strange.

The price is not very different between a 9 k and 12 k BTU. Will the larger 12K use more energy or just cool faster? Thinking on the lines of burning calories, walking 5 kms and running 5 kms burns the same amount of calories, running just gets you there faster (and cardio).

With the advent of inverter AC units the huge disadvantages of oversized units has become much less important. 
 

With a conventional unit oversizing is a very bad idea as there’s not enough run time to dehumidify before the cooling shuts off.
 

I haven’t seen good studies on the details of the exact way inverter units function so don’t know if the dehumidification still runs as the fans slow down.

 

I have found that even with minimum insulation 550BTU per square meter with a conventional AC and about 2.5 metre ceilings is enough. Others will want “sweater temperatures” so will need 800BTU SQ/M

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1 hour ago, Sakeopete said:

The price is not very different between a 9 k and 12 k BTU. Will the larger 12K use more energy or just cool faster? Thinking on the lines of burning calories, walking 5 kms and running 5 kms burns the same amount of calories, running just gets you there faster (and cardio).

There is probably not much difference between 9k and 12k "inverter" except price.  They will both normally run between 400-600 W. except on the hottest days.  The only time my 11k BTU Daikin runs at full bore is when I put on "Super Cool".  

 

BTW:  Walking fast or slow for the same distance will burn the same calories.  Running will be roughly double.

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6 hours ago, Sakeopete said:

We have a 4000 watt unit now and it get very hot if the tap isn't opened all the way. Otherwise my kids will stay in the shower until the storage tank runs dry.

 

Just turn off the breaker, that will bet them out. Been there, done that....

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"It's only temporary" can be a dangerous and costly phrase. I have seen many folks use local logic on what size "temporary meter" and worse, "what side cable from the PEA supply to their temporary meter".  I won't comment on metal poles.  I have seen half a dozen water pump motors ruined by voltage drop where folks realized they needed water to build a house. They thought to drill a well. Buy a cheap pump, but not have proper protection for the pump. Especially submersible well pumps with no proper control box.  Not just the standard "included" control box. The building team uses a welder, a few tools, an electric concrete mixer and the draw is too great on the WRONG undersized "It's only temporary" cable.  The pump motor is shot. There was low voltage arriving at the construction site due to undersized cable from the PEA supply. Costly mistake in my book, when so easy to avoid. The PEA office has charts showing MINIMUM size copper cable and MINIMUM size showing aluminum cable for service form the PEA connection to the home meter. Then the consumer should calculate the size of the cable form the METER to the load center, even if only a temporary construction meter and temporary electric socket job site box. Undersized electric cable can be a costly mistake in my observation. 

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