ZU/ZT-46
ZU/ZT
ZT1R5 ZT3
2.2 Overcurrent protection
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Overcurrent protection circuit is built-in and comes into effect at
over 105% of the rated current.
Overcurrent protection prevents the unit from short circuit and
over current condition of less than 20 sec. The unit automatically
recovers when the fault condition is cleared.
The power supply which has a current foldback characteristics
may not start up when connected to nonlinear load such as lamp,
motor or constant current load. See the characteristics below.
Fig.2.1 Current foldback characteristics
Note: In case of nonlinear load, the output is locked out at A point.
: Load characteristics of power supply
: Characteristics of load (lamp, motor, constant current load, etc.)
2.3 Isolation
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For a receiving inspection, such as Hi-Pot test, gradually increase
(decrease) the voltage for the start (shut down). Avoid using Hi-
Pot tester with the timer because it may generate voltage a few
times higher than the applied voltage, at ON/OFF of a timer.
3 Wiring to Input/
Output Pin
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Input filter is built-in. A capacitor Ci, if installed near the input ter-
minal, will lower the input conducted noise from converter due to
the formation of the
type filter.
When the distance from the DC line to the unit is greatly ex-
tended, it makes the input feedback noise much higher and the in-
put voltage several times higher than the normal level when
turned ON. If this happens, the output power also becomes un-
stable. In order to prevent the unit form failing in this way; please
connect Ci to the input terminal. In addition, when the filter with
L is used, please Ci to the input terminal.
” ”
Fig.3.1 Connecting method of capacitor at input terminal
Capacity of external capacitor at input terminal: Ci [µF]
Model
ZTS1R5
ZTW1R5
100
47
33
10
ZTS3
ZTW3
220
100
47
22
5
12
24
48
Input voltage(V)
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To lower the output ripple voltage further, install an external ca-
pacitor Co at output terminal as shown below.
ZTS
ZTW
Fig.3.2 Connecting method of external capacitor at output terminal
Capacity of external capacitor at output terminal: Co [µF]
Model
ZTS1R5
ZTW1R5
100
100
100
ZTS3
ZTW3
220
100
100
5
12
15
Output voltage(V)
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When the distance between load and DC output is long, please in-
stall capacitor at load as shown below.
Fig.3.3 Connection method of capacitor at load
+VIN
-VIN
DC IN
+VIN
-VIN
DC IN
(a)
(b)
Reverse input voltage protection
Avoid the reverse polarity input voltage. It will damage the power
supply.
It is possible to protect the unit from the reverse input voltage by
installing an external diode as shown in Fig.3.4.
Fig.3.4 Reverse input voltage protection
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Instruction
anual
M
DC-DC Converters PCB Mount type
