Multiquip MQP30DZ Genset Sizing Determining Load Characteristics, Single-Phase Induction Motor

GENSET SIZING — DETERMINING LOAD CHARACTERISTICS

Determining Load Characteristics

Lighting

For all types of lighting loads:

RkW = The sum of the rated watts of all lamps and ballasts.

Typical ballast wattages are defined by Table 2 below:

Table 2. Ballast Wattages

LAMP	BALLAST
48 inch T-12, 40 W, Preheat	10 W
48 inch T-12, 40 W, Rapid Start	14 W
High Output 40 W Fluorescent	25 W
Mercury, 100 W	18-35 W
Mercury, 400 W	25-65 W

For all types of lighting loads, except for high intensity discharge (HID), use the following:

SkW = RkW

Due to the starting characteristics of HID lighting, assume that

SkW = 0.75 x RkW

Unless otherwise known, assume the following starting and running power factors (SPF and RPF, respectively, see Table

3 below) for the following types of lighting:

Table 3. Starting & Running Power Factor

Type of Lighting	SPF	RPF
Fluorescent	0.95	0.95
Incandescent	1.00	1.00
High Intensity Discharge	0.85	0.90

Then the following can be calculated:

Single-Phase Induction Motor

For 1Ø motors, use the SkVA, SkW, RkVA, and RkW values in Table 4 below that correspond to the motor nameplate horsepower and type.

Table 4. Single Phase Motor Characteristics

HP	RkW	RkVA	SkVA	SkW
		Split Phase
1/6	0.3	0.5	3.5	2.8
1/4	0.4	0.6	4.8	3.8
1/3	0.5	0.7	5.6	4.5
1/2	0.7	0.9	7.7	6.1
	Capacitor Start / Induction Run
1/6	0.3	0.5	2.6	2.0
1/4	0.4	0.6	3.3	2.6
1/3	0.5	0.7	3.9	3.1
1/2	0.7	0.9	5.3	4.25
3/4	1.0	1.25	7.1	5.7
1	1.2	1.6	9.5	7.6
1-1/2	1.6	2.0	14.25	11.4
2	2.2	2.7	19	15.2
3	3.3	4.1	28.5	22.8
	Capacitor Start / Capacitor Run
1/6	0.3	0.5	2.8	2.3
1/4	0.4	0.6	3.8	3.0
1/3	0.5	0.7	3.6	2.9
1/2	0.7	0.9	5.9	4.7
3/4	1.0	1.25	8.0	6.4
1	1.2	1.6	10.6	12.7
1-1/2	1.6	2.0	16.0	12.7
2	2.2	2.7	21.2	17.0
3	3.3	4.1	31.8	25.5
	Permanent Split Capacitor (PSC)
1/6	0.3	0.5	1.0	0.8
1/4	0.4	0.6	1.5	1.2
1/3	0.5	0.7	2.0	1.6
1/2	0.7	0.9	3.0	2.4

PAGE 22 — INDUSTRIAL GENERATOR SETS — APPLICATION & INSTALLATION MANUAL — REV. #4 (09/07/07)