RTW281R8 TDK Corporation, RTW281R8 Datasheet - Page 16

• Manufacturer Part Number: RTW281R8
• Description: POWER SUPPLY IND 28V 1.8A 50.4W
• Manufacturer: TDK Corporation
• Series: RTWr

Specifications of RTW281R8

• Voltage - Output: 28V
• Number Of Outputs: 1
• Power (watts): 50W
• Applications: Commercial
• Power Supply Type: Switching (Open Frame)
• Voltage - Input: 85 ~ 265VAC
• Mounting Type: Chassis Mount
• 1st Output: 28 VDC @ 1.8A
• Size / Dimension: 4.88" L x 0.87" W x 3.23" H (124mm x 22.1mm x 82mm)
• Power (watts) - Rated: 50.4W
• Operating Temperature: -10°C ~ 71°C
• Efficiency: 85%
• Approvals: CE, CSA, cUL, EN, UL
• Line Regulation: 0.2%
• Load Regulation: 0.4%
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• 3rd Output: -
• 2nd Output: -
• 4th Output: -
• Other names: RTW28-1R8

Characteristics, Functions, and Applications
INSTALLATIONS
There are (B), (C), (D), and (E) besides standard installation
method (A) when the power supply is mounted on the device.
Because heat shuts oneself up internally in the power supply, the
installation of (D) and (E) cannot be used.
Please use the installation of (A), (B), and (C) within the range of
DERATING CURVE.
REMOTE SENSING
Remote Sensing compensates to provide stability at the load ter-
minal when voltage drop in the line between the power supply and
the load causes instability. Remote sensing is possible if the volt-
age drop per wire between the output and load terminals is 0.25V
max. for 5.0V models, 0.15V max. for 3.3V models and 0.4V max.
for 12 to 48V models.
Make sure that the power supply’s output voltage and power
remains within the range of the output specifications. Pulse loads
and other situations where sudden changes in the load can occur
may not conform to the dynamic load change specifications.
Take out the short-circuit plates of the +S/+ terminal and the –S/–
terminal and wire them as shown in the figure below. The sensing
lines must be either shielded or twisted (The recommended length
is 5m max.).
In case of parasitic oscillation or overvoltage protection malfunc-
tion too easily, install an external electrolytic capacitor, rated
470µF min. between the +OUT, +S and OUT, –S terminals.
• All specifications are subject to change without notice.
+S
–S
( D )
(A) Standard installation
+
–
+
+
Twisted(Stranded wire)
( B )
( E )
Load
( C )
REMOTE CONTROL(50 to 100W)
Turn the remote on/off switch located at the center of the power
supply to "Y" (clockwise) to enable the remote control.
The output voltage can be turned on and off from an external
source by inputting the signal indicated below between the remote
on/off terminals (+RC and –RC).
Output voltage is turned on when the level is high between the
+RC and –RC terminals (external voltage application of 4.5 to
24.5V).
Output voltage is turned off when the level is low between the +RC
and –RC terminals (short or terminal voltage of 0 to 0.8V).
∗
±RC terminals are insulated from AC input terminals and the DC
output terminals.
Insulation between the ±RC terminals and the output conforms to
the common specifications (Output to case). Withstand voltage
between AC input terminals and ±RC terminals conforms to the
common specifications (Input to case).
REMOTE ON-OFF(300W)
Output voltage On-Off can be controlled externally by inputting the
following signals to the (+RC, –RC) pins of function connectors
CN2 and CN3. The +RC pins are connected by a cable kit during
shipping remove the cable kit when using the Remote Control
Function.
Output voltage is turned off when the level is high between the
+RC and –RC terminals (open or external voltage application of
2.4 to 24V: input current 1.0mA max.).
Output voltage is turned on when the level is low between the +RC
and –RC terminals (short or terminal voltage of 0 to 0.4V: output
current 1.6mA max.).
±RC terminals are insulated from AC input terminals and the DC
output terminals.
Insulation between the ±RC terminals and the output conforms to
the common specifications (Output to case). Withstand voltage
between AC input terminals and ±RC terminals conforms to the
common specifications (Input to output).
External
voltage
Use an external resistor (1.5k
age of 12.5 to 24.5V.
∗
R
Input and output terminals
SW
+RC
–RC
+S
–S
G
N
Ω
+
–
L
) when applying an external volt-
004-02 / 20060214 / ea111_rtw.fm
Turn the internal switch to "Y."
N
Y
(16/19)