KEPCO RAX 50W User Manual
Kepco, 50 watt single output switching power supplies, I — introduction
©2000, KEPCO, INC
1
Data subject to change without notice
228-1225 REV 2
I N S T R U C T I O N M A N U A L
RAX
KEPCO
KEPCO, INC. !"! 131-38 SANFORD AVENUE !" FLUSHING, NY. 11352 U.S.A.!" TEL (718) 461-7000!"! FAX (718) 767-1102!!
http://www.kepcopower.com "! email: [email protected]
An ISO 9001 Company.
50 WATT SINGLE OUTPUT
SWITCHING POWER SUPPLIES
I — INTRODUCTION
SCOPE OF MANUAL. This instruction manual covers the installation and operation of the Kepco RAX 50W Series of Switching
Power Supplies. For service information, please refer to the Service Manual for the RAX 50W Series, which can be purchased
either from your Kepco Representative, or by writing directly to: Kepco Inc. 131-38 Sanford Avenue, Flushing, New York 11352,
U.S.A. When ordering a Service Manual, please state Model Designation and Serial Number of your RAX power supply.
This information can be found on the nameplate of the unit.
DESCRIPTION. The Kepco RAX 50W Series consists of seven models of switching power supplies, with a single output as
shown in Table 1. Units may be operated with either 115V a-c or 230V a-c 47-440Hz input. They will also operate on 240V to
370V d-c input. The RAX 50W Series employs a light weight ferrite core with 140 KHz switching frequency. Regulation is pro-
vided by pulse width modulation. A FET power stage, operating in the forward conversion mode provides a smooth isolated d-c
output. A triac “soft-start” circuit prevents excessive turn-on current surge. Overvoltage protection and optically isolated remote
TTL on-off control is provided. Current limiting with automatic recovery from short circuit is featured. Units are enclosed in a
wrap-around aluminum case with an LED “output present” light visible on the terminal side of the case.
Table 1 contains specifications and operating limits of individual RAX 50W Series models. Section II (following) contains specifi-
cations and operating limits common to all RAX 50W Series Models.
II — SPECIFICATIONS
The following specifications are at nominal input voltages at 25°C unless otherwise specified.
INPUT VOLTAGE: (Jumper selectable, see Section III, FIG. 3):
120V a-c nominal, range: 85 -132V a-c
220-240V a-c nominal, range: 170 -264V a-c
320V d-c nominal, range: 240 -370V d-c
For d-c input the jumper is placed in the 230V position.
INPUT SOURCE FREQUENCY:
Nominal 50/60 Hz; Range 47-440 Hz. (At 400 Hz the leakage current exceeds the VDE safety specification limit.)
TABLE 1. OUTPUT RATINGS AND SPECIFICATIONS, RAX 50W SERIES
MODEL
RAX 3.3-10K
RAX 5-10K
RAX 12-4.2K
RAX 15-3.4K
RAX 24-2.1K
RAX28-1.8K
RAX 48-1K
OUTPUT VOLTS, d-c
3.3V
5V
12V
15V
24V
28V
48V
ADJUSTMENT RANGE
1.8 - 3.6V
4.0 - 5.5V
8.4 - 13.2V
12.0 - 16.5V
16.8 - 26.4V
19.6 -30.8V
32.6 - 52.8V
MAXIMUM
OUTPUT
RATINGS
(AMPS,
WATTS)
50° C amb.
10.0A/33W
10.0A/50W
4.2A/50.4W
3.4A/51W
2.1A/50.4W
1.8A/50.4W
1.0A/48W
60° C amb.
7.0A/23.1W
7.0A/35W
2.9A/35.3W
2.4A/35.7W
1.5A/35.3W
1.3A/35.3W
0.7A/33.6W
71° C amb.
4.0A/13.2W
4.0A/20W
1.7A/20.1W
1.4A/20.4W
0.8A/20.1W
0.72A/20.2W
0.4A/19.2W
CURRENT LIMIT (AMPS)
(1)
10.5 -11.0
10.5 -11.0
4.5 - 4.8
3.6 - 3.9
2.3 - 2.5
2.0 - 2.2
1.1 - 1.3
OVP RANGE (VOLTS)
3.9 - 4.8
6.0 - 6.9
13.7 - 15.7
17.0 - 19.5
27.0 - 30.5
32.0 - 35.0
55.0 - 63.0
RIPPLE
AND
NOISE
(2)
(mV p-p)
source (typ)
5
5
15
15
25
30
35
source (max)
10
10
30
30
40
60
90
switching (typ)
25
25
25
25
25
25
25
switching (max)
40
40
50
50
60
60
60
spike noise
(max)
(3)
100
100
170
200
290
330
530
(1)
Change of current setting with the specified variations for operating temperatures and source input voltage is within ±10% of the rated values.
(2)
Source component 2x source frequency, and switching component approximately 140KHz.
(3)
Measured with a 50 MHz bandwidth.
CAUTION: UNIT IS SET
TO 115V AC OPERATION