KEPCO RTW 50W - Manual

©2011, KEPCO, INC 1
Data subject to change without notice 228-1510 REV 7
I N S T R U C T I O N M A N U A L
KEPCO
KEPCO, INC. " 131-38 SANFORD AVENUE " FLUSHING, NY. 11355 U.S.A. " TEL (718) 461-7000 " FAX (718) 767-1102
http://www.kepcopower.com " email: [email protected]
An ISO 9001 Company.
RTW
50W
50 WATT SINGLE OUTPUT, PFC,
OPEN FRAME POWER SUPPLIES
I — INTRODUCTION
SCOPE OF MANUAL. This instruction manual covers the installation and operation of the Kepco RTW 50W Series of Open Frame PFC
(Power Factor Corrected) RoHS (Reduction of Hazardous Substances) compliant Switching Power Supplies.
DESCRIPTION. The Kepco RTW 50W Series consists of seven models of switching power supplies, with a single output as shown in Table
1. Units may be operated with a nominal 100 to 120V a-c and 220 to 240V a-c (input voltage range 85 to 265 Va-c), 50-60 Hz (input frequency
range 47-440Hz; units operate up to 440Hz although leakage current, power factor and efficiency specifications may not be met)). They will
also operate on 120V to 370V d-c input. The RTW 50W Series employs a forward converter with a fixed switching frequency of 190KHz.
Power Factor Correction (PFC) is provided by a boost converter. Regulation is provided by pulse width modulation. A thermistor circuit pre-
vents excessive turn-on current surge. Remote on-off and remote programming of output voltage using an external resistance can be imple-
mented. Overvoltage and overcurrent protection is provided. Current limiting with automatic recovery from short circuit is featured. Units are
convection cooled L-chassis construction. Models with a factory-installed steel cover are indicated by a C suffix following the model number
(e.g., RTW 5-10KC).
Section II contains specifications and operating limits of individual RTW 50W Series models (Table 1) as well as specifications and operating
limits common to all RTW 50W Series Models. Section III describes installation and Section IV describes operation
II — SPECIFICATIONS
The following specifications are at rated input voltages at 25°C unless otherwise specified.
INPUT VOLTAGE:
Nominal 100-120V a-c, 220-240V a-c, range: 85-265V a-c (0 to 100% load, -10 to 71°C);
d-c range: 120 -370V d-c; polarity insensitive. Safety agency approval applies only to a-c input operation.
INPUT SOURCE FREQUENCY:
Nominal 50/60 Hz; Range 47-440 Hz (0 to 100% load, -10 to 71°C). (Units operate up to 440 Hz, however the leakage current exceeds
the UL leakage safety specification limit, and power factor and efficiency specifications may not be met.)
INPUT CURRENT:
0.7A rms max. (100-120 Va-c input, 100% load); 0.4A rms max. (200-240 Va-c input, 100% load).
3.3V model: 0.6A rms max. (100-120 Va-c input, 100% load); 0.3A rms max. (200-240 Va-c input, 100% load).
INPUT PROTECTION AND SOFT START: A thermistor circuit reduces start-up surge. Units are protected against shorts by an input
fuse. Fuse value 2A, 250V (Wickmann P/N C1-372-2.0A, Kepco P/N 541-0136).
INPUT SURGE: cold start 25 °C (First surge only, not including the current flow into the EMI filter)
14A typ. (100 V a-c, 100% load); 28A typ. (200 Va-c, 100% load).
TABLE 1. OUTPUT RATINGS AND SPECIFICATIONS, RTW 50W SERIES
MODEL
(6) RTW 3.3-12K RTW 5-10K RTW 12-4.3K RTW 15-3.5K RTW 24-2.2K RTW 28-1.8K RTW 48-1.1K
OUTPUT VOLTAGE SETTING, d-c 3.3 ±0.03V 5 ±0.05V 12 ±0.12V 15 ±0.15V 24 ±0.24V 28 ±0.28V 48 ±0.48V
ADJUSTMENT RANGE, Vd-c 2.60-4.0 4.0-5.8 9.6-13.2 12-16.5 19.2-26.4 22.4-30.8 38.4-52.8
OUTPUT CURRENT, MAX (AMPS) 12.5 10 4.3 3.5 2.2 1.8 1.1
OUTPUT POWER, MAX
(3)
(WATTS) 41.2 50 51.6 52.5 52.8 50.4 52.8
OVP SETTING
(1)
(VOLTS)
4.2-5.2 6.0-6.9 13.7-15.7 17.0-19.0 27.0-30.5 32.0-35.0 55.0-60.0
OVERCURRENT SETTING
(2)
(AMPERES)
10.5-12.5 10.5-12.5 4.5-5.4 3.68-4.38 2.3-2.75 1.9-2.25 1.15-1.38
SHORT CIRCUIT CURRENT
(AMPERES) (typ)
15.5 13 5.6 4.5 3.0 2.5 1.7
EFFICIENCY
100 Va-c 75% 80% 81% 82% 82% 82% 82%
200 Va-c 77% 82% 83% 85% 85% 85% 85%
RIPPLE AND
NOISE
(4)
(mV p-p)
Switching ripple (typ) 80 80 100 100 150 150 200
spike noise (typ)
(4) 120 120 150 150 200 200 300
External Potentiometer
(5) 250 Ohms 250 Ohms 500 Ohms 500 Ohms 1K Ohms 1K Ohms 2K Ohms
(1) An overvoltage shuts down the output. Recover by recycling a-c input (30 second delay required before resetting).
(2) Square type. After the cause of overcurrent is removed, output voltage recovers automatically.
(3) See Figure 2 for temperature and input voltage rating.
(4) Bandwidth 100MHz. Ripple and noise will be approximately 1.5 times these values in the operating temperature range -10 ~ 0°C. The ripple and noise
values tabulated are valid when the output is derated as shown in figure 2 from 40 ~ 71°C.
(5) Used for remote programming of output voltage. See Section IV OPERATION, REMOTE VOLTAGE PROGRAMMING.
(6) Specifications are identical for models either K or KC suffix