View source for ElectricalCapacityDC

{{#TwitterFBLike:right|small|like}}

= Calculating DC Electrical Capacity =

== Summary ==

Calculating DC (direct current) load for the [[DCPrimarySystem|DC primary system]] is an activity in determining the capacity of the boat's house bank of DC batteries. Over estimating the numbers to provide comfort in the individual calculations is not recommended. It is better to add spare capacity calculations directly to the [[:Category:ElectricalPrimarySupply|house bank]] specifications.<ref>http://www.powerstream.com/battery-capacity-calculations.htm</ref> <ref>http://web.mit.edu/evt/summary_battery_specifications.pdf</ref>

A link to a spreadsheet is provided.

== DC Load ==

<div id="spreadsheet"><i>Download spreadsheet:</i> [[Media:CalculatedLoadDC.xlsx|Microsoft Office xlsx]] | [[Media:CalculatedLoadDC.ods|Libre/Open Office ods]]</div>


<table border="1" style="width:90%">
<tr><th>ITEM	</th><th>	NUMBER	</th><th>	AMPS	</th><th>	AMPS <br>TOTAL	</th><th>	HOURS <br>PER DAY	</th><th>	DUTY <br>CYCLE	</th><th>	AMP <br>HOURS	</th></tr>
<tr><td colspan="7">	FIXED LOADS	</td></tr>												
<tr><td colspan="7"><b>	Cabins	</b></td></tr>												
<tr><td colspan="7">	Electronic Equipment	</td></tr>												
<tr><td style="text-align:right"><i>	Radio Transmitter	</i></td><td>	1	</td><td>	0.0	</td><td>	0.0	</td><td>	2.0	</td><td>	8%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	SSB	</i></td><td>	1	</td><td>	0.0	</td><td>	0.0	</td><td>	1.0	</td><td>	4%	</td><td>	0.0	</td></tr>
<tr><td colspan="7">	Ventilation	</td></tr>												
<tr><td style="text-align:right"><i>	Forward Cabin	</i></td><td>	10	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	Aft Cabin	</i></td><td>	2	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	Heads	</i></td><td>	2	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	Galley	</i></td><td>	1	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	Pilot House	</i></td><td>	2	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	Salon	</i></td><td>	2	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td bgcolor="#FF0000" colspan="7">	</td></tr>													
<tr><td colspan="7">	Instruments	</td></tr>												
<tr><td style="text-align:right"><i>	Alarm System (stnby)	</i></td><td>	0	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	Autopilot	</i></td><td>	0	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	Depth Sounder	</i></td><td>	1	</td><td>	0.0	</td><td>	0.0	</td><td>	24.0	</td><td>	100%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	Radar	</i></td><td>	1	</td><td>	0.0	</td><td>	0.0	</td><td>	24.0	</td><td>	100%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	GPS	</i></td><td>	1	</td><td>	0.0	</td><td>	0.0	</td><td>	24.0	</td><td>	100%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><b>	SubTotal 	</b></td><td>		</td><td>		</td><td>		</td><td>		</td><td>		</td><td>	0.0	</td></tr>
<tr><td bgcolor="#FF0000" colspan="7">	</td></tr>													
<tr><td colspan="7">	Machinery	</td></tr>												
<tr><td>	Navigation Lights	</td><td>	1	</td><td>	5.0	</td><td>	5.0	</td><td>	24.0	</td><td>	100%	</td><td>	5.0	</td></tr>
<tr><td>	Bilge Blowers	</td><td>	0	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td>	Bilge Pumps	</td><td>	0	</td><td>	0.0	</td><td>	0.0	</td><td>	1.0	</td><td>	4%	</td><td>	0.0	</td></tr>
<tr><td>	Wipers	</td><td>	0	</td><td>	0.0	</td><td>	0.0	</td><td>	24.0	</td><td>	100%	</td><td>	0.0	</td></tr>
<tr><td>	Searchlight	</td><td>	0	</td><td>	0.0	</td><td>	0.0	</td><td>	1.0	</td><td>	4%	</td><td>	0.0	</td></tr>
<tr><td>	Instruments	</td><td>	0	</td><td>	0.0	</td><td>	0.0	</td><td>	24.0	</td><td>	100%	</td><td>	0.0	</td></tr>
<tr><td>	Ventilation - Engine	</td><td>	2	</td><td>	0.0	</td><td>	0.0	</td><td>	24.0	</td><td>	100%	</td><td>	0.0	</td></tr>
														
<tr><td style="text-align:right"><b>	SubTotal 	</b></td><td>		</td><td>		</td><td>		</td><td>		</td><td>		</td><td>	5.0	</td></tr>
<tr><td bgcolor="#FF0000" colspan="7">	</td></tr>													
<tr><td>	Other	</td><td>	0	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%		</td></tr>
<tr><td style="text-align:right"><b>	SubTotal	</b></td><td>		</td><td>		</td><td>		</td><td>		</td><td>		</td><td>	0.0	</td></tr>
<tr><td>	Total Fixed	</td><td></td>	<td></td><td></td><td></td><td></td>	<td>									5.0	</td></tr>
<tr><td bgcolor="#FF0000" colspan="7">	</td></tr>													
<tr><td colspan="7">	INTERMITTENT LOADS	</td></tr>												
<tr><td colspan="7">	Cabins	</td></tr>												
<tr><td colspan="7">	Cabin Lighting	</td></tr>												
<tr><td style="text-align:right"><i>	Halogen 10 W	</i></td><td>	5	</td><td>	0.8	</td><td>	4.0	</td><td>	6.0	</td><td>	25%	</td><td>	1.0	</td></tr>
<tr><td style="text-align:right"><i>	Halogen 20 W	</i></td><td>	32	</td><td>	1.6	</td><td>	51.2	</td><td>	6.0	</td><td>	25%	</td><td>	12.8	</td></tr>
<tr><td style="text-align:right"><i>	Halogen 35 W	</i></td><td>	0	</td><td>	2.9	</td><td>	0.0	</td><td>	6.0	</td><td>	25%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	3 LED Reading Light	</i></td><td>	0	</td><td>	0.03	</td><td>	0.0	</td><td>	3.0	</td><td>	13%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	6 LED Reading Light	</i></td><td>	0	</td><td>	0.06	</td><td>	0.0	</td><td>	3.0	</td><td>	13%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	9 LED Reading Light	</i></td><td>	10	</td><td>	0.09	</td><td>	0.9	</td><td>	3.0	</td><td>	13%	</td><td>	0.1	</td></tr>
<tr><td style="text-align:right"><i>	10 W Fluorescent	</i></td><td>	0	</td><td>	0.80	</td><td>	0.0	</td><td>	6.0	</td><td>	25%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	13 W Fluorescent	</i></td><td>	0	</td><td>	0.80	</td><td>	0.0	</td><td>	6.0	</td><td>	25%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	15 W Fluorescent	</i></td><td>	0	</td><td>	1.20	</td><td>	0.0	</td><td>	6.0	</td><td>	25%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	18 W Fluorescent	</i></td><td>	0	</td><td>	1.50	</td><td>	0.0	</td><td>	6.0	</td><td>	25%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	20 W Fluorescent	</i></td><td>	0	</td><td>	1.60	</td><td>	0.0	</td><td>	6.0	</td><td>	25%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	26 W Fluorescent	</i></td><td>	0	</td><td>	2.10	</td><td>	0.0	</td><td>	6.0	</td><td>	25%	</td><td>	0.0	</td></tr>

<tr><td style="text-align:right"><b>	SubTotal Lights	</b></td><td>		</td><td>		</td><td>		</td><td>		</td><td>		</td><td>	13.9	</td></tr>
<tr><td bgcolor="#FF0000" colspan="7">	<tr><td bgcolor="#FF0000" colspan="7"> </td></tr> 													
<tr><td>	Cigarette Lighter	</td><td>	0	</td><td>	0.0	</td><td>	0.0	</td><td>	1.0	</td><td>	4%	</td><td>	0.0	</td></tr>
<tr><td colspan="7">	Electronic Equipment	</td></tr>												
<tr><td style="text-align:right"><i>	SW Receiver	</i></td><td>	1	</td><td>	0.0	</td><td>	0.0	</td><td>	1.0	</td><td>	4%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><i>	Stereo - Saloon	</i></td><td>	1	</td><td>	8.3	</td><td>	8.3	</td><td>	12.0	</td><td>	50%	</td><td>	4.2	</td></tr>
<tr><td style="text-align:right"><i>	Stereo - Dinette	</i></td><td>	1	</td><td>	8.3	</td><td>	8.3	</td><td>	12.0	</td><td>	50%	</td><td>	4.2	</td></tr>
<tr><td style="text-align:right"><i>	Stereo - Main Cabin	</i></td><td>	1	</td><td>	8.3	</td><td>	8.3	</td><td>	4.0	</td><td>	17%	</td><td>	1.4	</td></tr>
<tr><td style="text-align:right"><i>	Microwave	</i></td><td>	0	</td><td>	68.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><b>	SubTotal Equipment	</b></td><td>		</td><td>		</td><td>		</td><td>		</td><td>		</td><td>	9.7	</td></tr>
<tr><td bgcolor="#FF0000" colspan="7">	<tr><td bgcolor="#FF0000" colspan="7"> </td></tr> 													
<tr><td colspan="7">	Machinery	</td></tr>												
<tr><td>	Trim Tabs	</td><td>	0	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td>	Horn	</td><td>	1	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td>	Anchor Windlass	</td><td>	0	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td>	Winches	</td><td>	0	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td>	Fresh water Pumps	</td><td>	1	</td><td>	0.0	</td><td>	0.0	</td><td>	2.0	</td><td>	8%	</td><td>	0.0	</td></tr>
<tr><td>	Air Conditioner	</td><td>	1	</td><td>	0.0	</td><td>	0.0	</td><td>	0.0	</td><td>	0%	</td><td>	0.0	</td></tr>
<tr><td>	Furnace - Diesel	</td><td>	1	</td><td>	7.5	</td><td>	7.5	</td><td>	7.0	</td><td>	29%	</td><td>	2.2	</td></tr>
<tr><td colspan="7">	Refrigeration	</td></tr>												
<tr><td style="text-align:right"><i>	Cold Plate	</i></td><td>	1	</td><td>	35.0	</td><td>	35.0	</td><td>	2.0	</td><td>	8%	</td><td>	2.9	</td></tr>
<tr><td style="text-align:right"><i>	Constant Cycling	</i></td><td>	0	</td><td>	7.0	</td><td>	0.0	</td><td>	8.0	</td><td>	33%	</td><td>	0.0	</td></tr>
<tr><td>	Sewage Pump	</td><td>	1	</td><td>	0.0	</td><td>	0.0	</td><td>	2.0	</td><td>	8%	</td><td>	0.0	</td></tr>
<tr><td style="text-align:right"><b>	SubTotal Machinery	</b></td><td>		</td><td>		</td><td>		</td><td>		</td><td>		</td><td>	5.1	</td></tr>
<tr><td bgcolor="#FF0000" colspan="7">	<tr><td bgcolor="#FF0000" colspan="7"> </td></tr> 													
	</table>

See also [[ElectricalCapacityAC]].

== Links ==


[[Category:ElectricalCapacity]]