
INSTRUCTION MANUAL
KEPCO
An ISO 9001 Company.
MTW
60 WATT TRIPLE OUTPUT
SWITCHING POWER SUPPLY
I — INTRODUCTION
SCOPE OF MANUAL. This instruction manual covers the installation and operation of the Kepco MTW 60W Switching Power Supply,
Model MTW 60-51212K.
DESCRIPTION. The Kepco MTW 60W is a PC card style, triple-output switching power supply. 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). They will also operate on
110V to 370V d-c input. The MTW 60W employs a light weight ferrite core with 70 KHz switching frequency for the +5V output and 100KHz for
the ±12V outputs. Regulation is provided by pulse width modulation. A FET power stage, operating in the flyback mode provides smooth isolated d-c outputs. A trimmer provides fine adjustment of the 5V output. The ±12V outputs have a common return. DC Output power is shared
between +5V, +12V and -12V (60W max. total). A thermistor circuit prevents excessive turn-on current surge. Overvoltage protection is provided. Overcurrent protection with automatic recovery from short circuit is featured. A steel cover (Model CA 41) is available as an option.
Table 1 contains output specifications. Section II (following) contains specifications and operating limits.
II — SPECIFICATIONS
The following specifications are at nominal input voltages at 25°C unless otherwise specified.
TABLE 1. MTW 60W OUTPUT SPECIFICATIONS
SPECIFICATION
OUTPUT VOLTS, d-c
SETTING TOLERANCE (V)
ADJUSTMENT RANGE
OUTPUT
CURRENT
(A)
SOURCE EFFECT
LOAD EFFECT
TEMPERATURE EFFECT
COMBINED EFFECT
TIME EFFECT (Drift)
OVERCURRENT (AMPS)
OVERVOLTAGE SETTING (VOLTS)
EFFICIENCY (typ.)
ACCEPTABLE OUTPUT CAP.
RIPPLE
AND
(1)
NOISE
(mV p-p)
(1) Switching component ≤ 20KHz, 0 to 100% load, 0 to 60
°C, tested with 100µF electrolytic and 0.1µF film capacitors across the load and connected to the power supply
via 5.9 in (150mm) wires.
(2) Hiccup type; automatic recovery after cause of overcur-
rent is removed. Avoid overcurrent operation to prevent
component degradation.
RATED
MINIMUM
(5)
PEAK
(2)
(3)
100 Va-c
240 Va-c
(4)
(µFmax.)
ripple (typ)
ripple (-10-0ªC)
spike noise (typ)
spike noise (-10-0ªC)
INPUT VOLTAGE: CAUTION: Operation at voltage below specified range for more than 10 minutes may cause component degradation.
Nominal 100-120V a-c, 200-240V a-c, range: 85-265V a-c (0 to 100% load, -10 to 60°C)
d-c range: 110 -370V d-c (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 60°C). At 440 Hz the leakage current exceeds the VDE safety specification
limit.
OUTPUT 1 OUTPUT 2 OUTPUT 3 CONDITON
5V +12 –12V +5V floating from ±12V
4.9-5.1
5.00-5.25
2.5% max. 2.5% max. 2% max. Overshoot at startup: 4% typ.
(6)
5.0 2.5 0.5
0 0 0
7.0 3.5 0.7 Within 10 seconds.
1% max. 0.4% max. 0.4% max. 85-132Va-c, 170-265Va-c
2% max. 2% max. 1% max. 10-100% load
2% max. 2% max. 1% max. -10 to 50°C
1% max. 1% max. 1% max. 1/2 to 8 hr.
7.4 min. 3.7 min. 0.75 min.
5.8 min. 13.8 min. 76% 76% 76%
76% 76% 76%
10000 5000 3000
80 100 100
140 max. 160 max. 160 max.
120 150 150
160 max. 180 max. 180 max.
11.4-12.6 11.4-12.6
FIXED FIXED
(3) Zener diode clamp method; protects load against faulty power supply;
operation could require power supply service.
(4) +5V output may drop during startup.
(5) Peak current acceptable as long as rms output current within 10 seconds is
within rated value.
(6) Adjustable using 5V Output Voltage Adjustment trimpot.
60W
Fixed load resistance
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INPUT CURRENT: (maximum load at 25°C with nominal output voltage):
1.4A typ. (100 Va-c input, 100% load); 0.8A typ. (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 3A, 250V.
INPUT SURGE: First surge only, not including current flow into EMI filter.
20A typ. (100 V a-c, 100% load, 25°C cold start); 40A typ. (240 Va-c, 100% load, 25°C cold start)
LEAKAGE CURRENT:
0.60mA max, 0.45mA typ at 100V a-c (single pole switching) in conformance to DENAN .
0.75mA max, 0.55mA typ at 240V d-c (single pole switching in conformance to UL 1950/IEC 950)
POWER FACTOR: 0.55 typ. at 100 Va-c, 0.45 typ. at 240 Va-c
TRANSIENT RECOVERY: A step load change from 50% to 100% of rated load in 50 microseconds or more, produces no more than
4% output voltage excursion. Temperature range from -10 to 60°C.
OUTPUT HOLDING TIME: Upon input interruption the output is maintained for 180 milliseconds typical with 240 Va-c input voltage,
and for 20 milliseconds typical with 100 Va-c input voltage. The condition for output load is 100%.
START UP TIME: 350mS max. (+5V, ±12V) at 100 Va-c, 150mS max. (+5V, ±12V) at 240 Va-c. Output voltage may not rise with con-
stant current load. Output voltage may rise momentarily, then drop during brief input voltage interruptions.
OVERVOLTAGE PROTECTION: Fixed, factory set. See Table 1. The overvoltage circuit is set by Zener diode clamp.
OVERCURRENT: Hiccup type, output voltage returns to rated level upon removal of cause (long term overcurrent could damage unit)
OPERATING TEMPERATURE: -10 to 60°C (start up -20 to -10°C). See the derating
plot, Figure 1. Do not allow the power supply to become dust covered because that will
decrease the cooling efficiency of the unit and cause insulation to deteriorate.
STORAGE TEMPERATURE: -30°C to + 75°C.
COOLING: Natural convection
ORIENTATION: Horizontal (see Figure 2).
HUMIDITY: 10% to 90% relative humidity, operating and storage, noncondensing,
wet bulb temperature ≤35°C
WITHSTANDING VOLTAGE:
(at 5 to 35°C ambient, 45 to 85% relative humidity, cutout current 10 ma):
Between input and output terminals, 3.0 KV a-c for 1 minute.
Between input and chassis, 2000V a-c for 1 minute.
Between output terminals and chassis, 500V a-c for 1 minute.
INSULATION RESISTANCE: (500V d-c, 5 to 35°C ambient, 45 to 85% relative humidity)
Between input and output, input and chassis, and output and chassis:100 megohms
minimum.
VIBRATION: Three axes, one hour each, sweep time 10 min:, nonoperating
2
5-10 Hz., 10 mm amplitude;10-200 Hz., 2G (19.6m/s
SHOCK: Three axes, 60G (588m/s
axis, nonoperating, 1/2 sine pulse
2
), 11 ms ±5msec pulse duration, three shocks each
) acceleration
FIGURE 1. DERATING PLOT
SAFETY: Meets UL 60950-1.c-UL and TÜV Rheinland EN60950 (ambient temp. 50°C max,). Meets creepage and clearance require-
ments of DENAN Appendix 8 (at 100V a-c only). MTW 60W units are CE marked per the Low Voltage Directive (LVD), EN60950. [The
standards do not apply with DC input operation]
EMC - EMISSIONS:
Conducted Noise 0.15MHz to 30MHz: FCC Class B, VCCI-B, EN55011-B, EN55022-B
EMC - IMMUNITY:
ESD: EN 61000-4-2 Level 4, Normal operation.
Radiated Field Noise: EN 61000-4-3 Level 3, Normal operation.
Electrical Fast Transient/Burst (EFT): EN 61000-4-4 Level 3, Normal operation.
Surge: EN 61000-4-5 Level 4, no damage.
Conducted Noise: EN 61000-4-6 Level 3, Normal operation.
Power Frequency Magnetic Field: EN 61000-4-8 Level 4, Normal operation.
Voltage Dips, Short Interruptions, Voltage Variation: EN 61000-4-11, Normal operation.
ELECTROLYTIC CAPACITOR: Life expectancy: 10,000 hours min. (ambient temp. 50°C)
WARRANTY: One year.
III — INSTALLATION
MOUNTING THE POWER SUPPLY: Refer to Figures 2, 3 and 4. The unit may be mounted on one mounting surface. The air sur-
rounding the power supply must not exceed the ambient temperature values given in the graph in Figure 1.
KEPCO, INC. 131-38 SANFORD AVENUE FLUSHING, NY. 11355 U.S.A. TEL (718) 461-7000 FAX (718) 767-1102
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INSTALLATION (INSULATION): Install unit 0.3 inches (8mm) away from base with the use of 0.24 inch (6mm) diameter spacers
attached to the PC board. Keep at least 0.16 inches (4mm) spacing around and above the unit to comply with insulation and safety requirements. An insulator must be used if the spacing is less than 0.16 inches (4mm) (see Figure 3).
VENTILATION: It is recommended to keep at least 0.40 inches (10mm) clearance from adjacent equipment for proper ventilation
CONNECTIONS: Connect a load to the +5V output of the power supply by connecting pin 7 of output connector CN2 (+5V) to the load (+)
terminal, and pin 6 (5V Return) to the load (–) terminal (see Figure 4 for input/output connector/pin locations). Connect a load to the +12V
output of the power supply by connecting pin 4 (+12V) of connector CN2 to the load (+) terminal, and pin 3 (±12V Return) to the load (–) terminal. Connect a load to the -12V output of the power supply by connecting pin 1 (–12V) of connector CN2 to the load (–) terminal, and pin 2
(±12V Return) to the load (+) terminal.The AC input power is applied via input connector CN1. Make sure to connect the AC input Neutral
and Line wires to pins 3 and 1, respectively, of CN1 (see Figure 2). See Table 2 for mating connector information. A Cable Kit (P/N 219-0487)
is available as an option from Kepco. The kit includes an input cable, terminated on one end with an input mating connector; and an output
cable, terminated on one end with an output mating connector.
FIGURE 2. MOUNTING DIRECTION
FIGURE 3. VENTILATION AND INSULATION REQUIREMENTS
KEPCO, INC. 131-38 SANFORD AVENUE FLUSHING, NY. 11355 U.S.A. TEL (718) 461-7000 FAX (718) 767-1102
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FIGURE 4. MTW 60W MECHANICAL OUTLINE DIAGRAM
TABLE 2. INPUT/OUTPUT MATING CONNECTORS
Connector MTW 60W Connector
Socket Housing Terminal Pin
(1)
(1)
VHR-5N
VHR8N
Input B3P5-VH-B
Output
NOTES:
1. Manufacturer: Japan, Solderless Terminal Mfg. Co. Ltd, VH Series
2. Optional cable kit (KIT 219-0487) includes one input and one output cable (one meter long) with mating connectors
for CN 1 (input) and CN2 (output), unterminated at other end.
B8P-VH-B
Mating Connector
(1)
(1)
(2)
SVH-21T-P1.1
SVH-21T-P1.1
(1)
(1)
TABLE 3. ACCESSORIES
Accessory Part Number
Cable Kit KIT 219-0487 Includes one input and one output cable
(one meter long) with mating connectors
for CN1(input) and CN2 (output), unterminated at other end
Enclosure CA 41 Galvanized Steel
CA 41-R Cold Rolled Steel with RoHS Compliant
Zinc finish
Description
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: hq@kepcopower.com
4 228-1546 REV 4 090712