3.17
Series Operation
◎
Higher output voltage can be acquired by connecting rack shelves in series.
The rack shelves (RHP-1U ) connected in series should have the identical units. Please refer to Figure3-9 for wiring
◎
configuration
.
Total output current should not exceed currents that can be produced in each rack shelf.
◎
Difference of rise time in each unit may lead to steps/stairs like turn on.
◎
The total amount of output voltage in series should be less than 60Vdc [the requirement of SELV (Safety Extra Low Voltage) of IEC60950-1].
◎
It is suggested that add external diodes (*) on the output, shown in Figure 3-9, to prevent reverse voltage. Rating of these diodes should be
◎
higher than the total amount of output voltage and current.
RHP-1U#1
RHP-1U#2
A
ON/OFF
3
7
11
15
19
21
+V
+S
-S
-V
B
ON/OFF
C
D
E
+5V-AUX
ON/OFF ON/OFF ON/OFF
+V
-V
LOAD
+V
+S
23
22
22
(*)
Figure 3-9 Configuration of rack shelf units in series
A
ON/OFF
3
7
11
15
19
21
B
ON/OFF
C
D
E
+5V-AUX
ON/OFF ON/OFF ON/OFF
-S
23
-V
(*)
11
◎
Parallel operation is only suitable for the identical units (with the same model and the same output voltage/current). Up to 3 rack shelves
and the maximum supply units that can be connected in parallel is 15.
Because of component tolerance, there is a possibility that some of the units connected in parallel will reach an overcurrent limiting then
◎
overloading the other units when operating at full load condition. It is suggested that reduce the total output current by 10%.
For example: RCP-1600-24x15 connected in parallel (in 3 rack shelves), the total output current should be
to 67Ax15unitx0.9
reduced
=904.5A
.
Difference of output voltage among parallel units should be less than 0.2V
.
◎
Co
rack shelf units in parallel before
ing to the load. Do not connect rack shelf units to the load separately. Refer to Figure 3-8
nfigure
connect
◎
Control singles of DA, DB and V should also be connected in parallel. (Refer to Figure 3.8).
–
◎
Use twisted wires for the wiring of +S and S, the twisted wires should not touch the load wires to avoid interference. Refer to Figure 3-8.
–
◎
A too long cable length might be with a higher amount of noise that affects rack units proper operation in parallel. To reduce the noise,
'
◎
installing termination resistors, an accessory, to the unused JK1 is recommended.
3.16.2
Operation of three rack shelves in parallel (RCP-1600 system)
JK1
JK1
CN1
-V
-V
DB
DB
DB
DA
DA
DA
+S
-S
+5V-AUX
+5V-AUX
ON / OFF-A
ON / OFF-A
ON / OFF-B
ON / OFF-C
+V
-V
}
}
+V
LOAD
RHP-1U#1
RHP-1U#2
ON / OFF-E
ON / OFF-D
CN2
CN1
ON / OFF-B
ON / OFF-C
ON / OFF-D
ON / OFF-E
+V
-V
-V
JK1
DA
DA
CN1
-V
DB
DB
+5V-AUX
ON / OFF-A
ON / OFF-B
}
RHP-1U#3
ON / OFF-C
ON / OFF-D
ON / OFF-E
+V
-V
Twisted wires
Figure 3-8 Configuration of three rack shelf units in parallel
◎
Under operation of more than one rack shelf in parallel, value of Ripple & Noise may be larger than that stated in the specification at light load or
no condition. It will return to normal level once the loads draw more current than 10% of the total rating.
13
RCB-1600-RHP-1U_1610-21407-0001-E-0420