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4
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11
TDK-Lambda
DBM20
INSTRUCTION MANUAL
PA640-04-01B
3. Terminal Connecting Method
Pay attention to the input/output wiring. If it is connected to
wrong terminal, the buffer module will be damaged.
When connecting input and output wiring, input
voltage should be off
The terminal must be connected to the
protective earth terminal or chassis of the equipment.
When connecting or removing input and output wires,
do not apply stress to unit.
Power supply should be fixed directly to the input
connector of the buffer module. Please refer to wiring
diagram shown in 3.1 below.
According to EN/UL62368-1 multi-strand flexible
cables connected to the input require ferrule.
3.1 Wiring for power supply and buffer
module.
(1) General input/output wiring
(2) Parallel of buffer units
(3) Signal wiring with internal voltage supply
(4) Signals wiring with external voltage supply
DBM20
1 Inhibit
4
3
2
1
4 +
3 Buffer
2 Ready
TD
Level
Buffer
VIN‐1
FIXED MODE
CHARGING
DISCHARGING
+V
24VDC/20A
+V
‐V
‐V
4. Explanation of Functions and Precautions
4-1. Input Voltage Range
4-1.1 Fixed mode: input voltage range is 23 – 30VDC.
4-1.2 VIN-1 mode: input voltage range is 24 – 30VDC
Input voltage which is out of specification or reversed,
may damage the unit.
4-2. Nominal Buffer Voltage Range
4-2.1 Fixed mode: during buffering mode the nominal
buffer voltage level : 22.4VDC.
4-2.2 VIN-1 mode: during buffering mode the
nominal buffer voltage range : 22 - 29.4 VDC (at
20A).
Caution on use :
Kindly take note that the buffer voltage is equal to the
input voltage during Ready mode.
4-3. Signal Output
4-3.1 Relay signal is present at the DC OK terminals as
indication of the status of input voltage at the input
terminal.
In normal operation relay DC OK is close if it is greater,
or open if it is lower then the threshold voltage : 18.8 ±
0.5V.
DC OK relay rating : 30V(max) / 200mA(max).
N
L
+
Buffer
Ready
Inhibit
DISCHARGING
CHARGING
24VDC/20A
+V
DBM20
1
+V ‐V ‐V
2
3
4
4 +
3 Buffer
2 Ready
1 Inhibit
DRF480‐24‐1
24VDC/20A
+V +V ‐V ‐V
DC OK
DC OK
V. ADJ
PEAK
100‐240VAC
N
L
TD
TD
FIXED MODE
VIN‐1
Buffer
Level
Figure 4
Figure 5
DISCHARGING
CHARGING
24VDC/20A
+V
DBM20
1
+V ‐V ‐V
2
3
4
4 +
3 Buffer
2 Ready
1 Inhibit
TD
FIXED MODE
VIN‐1
Buffer
Level
DC OK
Figure 2
Figure 3
N
L
+
Buffer
Ready
Inhibit
DISCHARGING
CHARGING
24VDC/20A
+V
DBM20
1
+V ‐V ‐V
2
3
4
4 +
3 Buffer
2 Ready
1 Inhibit
DISCHARGING
CHARGING
24VDC/20A
+V
DBM20
1
+V ‐V ‐V
2
3
4
4 +
3 Buffer
2 Ready
1 Inhibit
DRF480‐24‐1
24VDC/20A
+V +V ‐V ‐V
DC OK
DC OK
V. ADJ
PEAK
100‐240VAC
N
L
TD
TD
TD
FIXED MODE
VIN‐1
Buffer
Level
FIXED MODE
VIN‐1
Buffer
Level
