Authority: IC 22-13-2-13

Affected: IC 22-12; IC 22-13; IC 22-14; IC 22-15

Sec. 100. (a) The following method shall be employed in computing the supply cord and distribution panelboard load for each feeder assembly for each mobile structure and shall be based on a three (3) wire, one hundred fifteen/two hundred thirty (115/230) volt supply with one hundred fifteen (115) volt loads balanced between the two (2) legs of the three (3) wire system.

1. (1) Method No. 1; Lighting and Small Appliance Load. Lighting Watts: Length times width of mobile structure (outside dimensions, exclusive of coupler) times three (3) watts per square foot; e.g., Length × Width × 3 = _____ lighting watts.

2. Small Appliance Watts: Number of circuits times one thousand five hundred (1500) volt amperes for each twenty (20) ampere appliance receptacle circuit (see definition of "appliance, small" with note); e.g., Number of circuits × 1500 = _____ small appliance volt-amperes.

   1. Total lighting watts plus small appliance = _____ total volt-amperes.
   2. First three thousand (3000) total volt-amperes at one hundred percent (100) plus remainder at thirty-five percent (35%) = _____ volt-amperes to be divided by two hundred thirty (230) volts to obtain current (amperes) per leg.

   3. Total load for determining power supply is the summation of:

      1. (A) Lighting and small appliance load is calculated in (a)(1).
      2. (B) Nameplate amperes for motors and heater loads (exhaust fans*, air conditioners*, electric gas, or oil heating.+)
      3. *Omit smaller of these two (2), except include blower motor if used as air-conditioner evaporator motor.
      4. +When an air conditioner is not installed and a forty (40) ampere power supply cord is provided, allow fifteen (15) amperes per leg for air conditioning.
      5. (C) Twenty-five percent (25%) of current of largest motor in item (B) above.
      6. (D) Total of nameplate amperes for: disposal, dishwasher, water heater, clothes dryer, wall-mounted oven, cooking units.
      7. Where number of these appliances exceed three (3), use seventy-five percent (75%) of total.

      8. (E) Derive amperes for free-standing range (as distinguished from separate ovens and cooking units) by dividing values below by two hundred thirty (230) volts.

         	Nameplate Rating	Use
         	10,000 w × or less	80% of rating
         	10,001 - 12,500 w	8,000 v-a
         	12,501 - 13,500 w	8,400 v-a
         	13,501 - 14,500 w	8,800 v-a
         	14,501 - 15,500 w	9,200 v-a
         	15,501 - 16,500 w	9,600 v-a
         	16,501 - 17,500 w	10,000 v-a

      9. (F) If outlets or circuits are provided for other than factory-installed appliances include the anticipated load.
      10. NOTE: The following example is given to illustrate the application of this Method of Calculation: EXAMPLE

      11. A mobile structure is 70 × 10 feet and has two (2) portable appliance circuits, a 1000 watt 230 volt heater, a 200 watt 115 volt exhaust fan, a 400 watt 115 volt dishwasher and a 7000 watt electric range.

          	Lighting and small appliance load.
          	Lighting 70 × 10 × 3 =			2100 v-a
          	Small appliance 1500 × 2 =			3000 v-a
          	Laundry 1500 × 1 =			1500 v-a
          				6600 v-a
          	1st 3000 at 100%			3000
          	Remainder (5100 - 3000 = 2000) @ 35%			1260
          				4260
          	4260	= 185 amperes per leg
          	230
          	1000 watt (heater) divided by 230 =			4.4 amp
          	200 watt (fan) divided by 115 =			1.7 amp
          	400 watt (dishwasher) divided by 115 =			3.5 amp
          	7000 watt (range) × .8 divided by 230 =			24.0 amp
          			Amperes Per Leg
          			A	B
          	Lighting and appliances		18.5	18.5
          	Heater (230 volt)		4	4
          	Fan (115 volt)		2	–
          	Dishwasher (115 volt)		–	4
          	Range		24	24
          	Totals		48.5	50.5

      12. Based on the higher current calculated for either leg, use one (1) fifty (50) ampere supply cord.

3. (2) Method No. 2; Optional Method of Calculation for Lighting and Appliance Loads. For mobile structures served by a single three (3) wire one hundred fifteen/two hundred thirty (115/230) volt set of feeder conductors with an ampacity of one hundred (100) or greater, the total load for determining the feeder ampacity may be computed in accordance with Table 100(a)(2) instead of the methods specified in (a)(1). Feeder conductors whose demand load is determined by this optional calculation shall be permitted to have the neutral load determined by section 220-22 of the Indiana Electrical Code ( 675 IAC 17-1 [ 675 IAC 17-1 was repealed filed Feb 17, 1987, 3:15 p.m.: 10 IR 1389, eff Mar 1, 1987 [ IC 4-22-2-36 suspends the effectiveness of a rule document for thirty (30) days after filing with the secretary of state. LSA Document #86-153 was filed Feb 17, 1987.].]). The loads identified in Table 6B, below as "other load" and as "remainder of other load" shall include the following:

   1. (A) One thousand five hundred (1500) watts for each two (2) wire, twenty (20) ampere small appliance branch circuit and each laundry branch circuit specified.
   2. (B) Three (3) watts per square foot for general lighting and general-use receptacles.
   3. (C) The nameplate rating of all fixed appliances, ranges, wall-mounted ovens, counter-mounted cooking units, and including four (4) or more separately controlled space heating units.
   4. (D) The nameplate ampere of kVA rating of all motors and all low-power factor loads.

   5. (E) The largest of the following: (i) air-conditioning load; (ii) the sixty-five percent (65%) diversified demand of the central electric space heating load; (iii) the sixty-five percent (65%) diviersified [sic.] demand of the load of less than four (4) separately-controlled electric space heating units; (iv) the connected load of four (4) or more separately controlled electric space heating units.

      TABLE 6B
      Optional Calculation for Mobile Structures with 100-Amperes or Larger Service
      Load (in kW or kVA)	Demand Factor (Percent)
      Air-conditioning and cooling, including heat pump compressor	100
      Central electric space heating	65
      Less than four (4) separately controlled electric space heating units	65
      First ten (10) kW of all other load	100
      Remainder of other load	40

(Fire Prevention and Building Safety Commission; 675 IAC 15-2-100; filed Mar 25, 1986, 1:44 pm: 9 IR 2022, eff Jun 15, 1986; errata, 9 IR 2931; errata, 9 IR 3093; readopted filed Nov 29, 2001, 12:21 p.m.: 25 IR 1306; readopted filed Sep 21, 2007, 9:20 a.m.: 20071010-IR-675070388RFA; readopted filed Oct 10, 2007, 9:16 a.m: 20071031-IR-675070388RFA; readopted filed Aug 4, 2011, 8:35 a.m.: 20110831-IR-675110254RFA; readopted filed Mar 10, 2017, 9:37 a.m.: 20170405-IR-675170005RFA; readopted filed May 11, 2023, 2:22 p.m.: 20230607-IR-675230104RFA)