INSTRUCTION MANUAL
ZWP350-1000 Series
TDK-Lambda
<Page>
11/23
6-9. Output Ripple and Noise
The standard specification for maximum ripple value is measured according to measurement circuit specified
by JEITA-RC9131D. In the case of the output lines become longer, the electrolytic capacitor and film
capacitor might be necessary to use across the load terminal to reduce output ripple and noise. If the probe
ground lead of oscilloscope is too long, the output ripple and noise cannot be measure accurately.
6-10. Series Operation
For series operation, either method (A) or (B) is possible.
Method (A)
Method (B)
Note : Never use in condition that one of the units is not operated. It will cause power supply to damage.
When power supplies are connected as method (A), the bypass diode is required. The bypass diode
must be selected with maximum forward current rating and maximum reverse voltage rating of
more than output current and output voltage.
6-11. Parallel Operation
Method (A), that to increase the output current is not possible. If redundancy is required for equipment,
protection diode must be inserted between power supply and load as Method (B).
If Method (B) is required, the following items should be considered.
1. Set the output voltage of power supplies higher by the forward voltage drop of protection diode.
2. Adjust the output voltage of each power supplies to be the same.
3. Use power supply within output voltage range and maximum output power in the standard specification.
4. Select protection diode with higher forward current rating than the output current.
Method (A)
Method (B)
POWER
SUPPLY
+
-
POWER
SUPPLY
+
-
LOAD
+
-
POWER
SUPPLY
+
-
POWER
SUPPLY
+
-
LOAD
+
-
POWER
SUPPLY
+V
-V
POWER
SUPPLY
+V
-V
LOAD
+
-
Bypass diodes
POWER
SUPPLY
+V
-V
POWER
SUPPLY
+V
-V
LOAD
+
-
LOAD
+
-
POWER
SUPPLY
LOAD
Oscilloscope
C1
C2
C3
R1
A
Coaxial Cable
1.5m 50Ω
Oscilloscope
Bandwidth : 100MHz
C1 : 0.1uF Cap., Film
C2 : 100uF Cap., Elect
C3 : 4700pF Cap., Cera
R1 : 50Ω
+
-
150mm
