IAI PSA-24, Instruction Manual

Page: 46 / 84

4.1 Specification Details
4-5
4.
O
per
at
io
n
If one load is connected without using the terminal block as shown in the figure below, the load current for the power supply unit
closer to the load increases and the voltage drop due to the cables becomes larger, creating an unbalanced output current. To
balance the cable voltage drop, always take out with the terminal block as shown in Figure 4.1.4 before connecting the load.
Figure 4.1.5 [Do not do this] Connections for parallel operation (One load)
■ Pay attention to the following points when wiring.
● Use the same type of wire (recommended size: AWG 14 to 18) for the crossover cable (between two power supply units
or between a power supply unit and terminal block) and keep the wire as short as possible while keeping lengths equal.
● Place the terminal block and each power supply unit close to the loa d, and use wires as thick
as possible and within the specifications required for the load.
● Always separate the wiring used for parallel connection of the power supply units and the wiring to the load.
● It is recommended to wire the positive and negative wires as twisted pairs.
■ When connecting multiple power supplies in parallel, the upper limit of the output current
characteristic should be 90%.
The number of parallel connected units and permissible current are summarized in the table below.
No. of connected units [unit] Rated current [A] Peak current [A]
1 8.5 17
2 15.3 30.6
3 22.95 45.9
4 30.6 61.2
5 38.25 76.5
1 unit: Rated current: 8.5 A / Peak current: 17 A
2 units: Rated current: 15.3 A (8.5 A x 0.9 x 2) / Peak current: 30.6 A (17 A x 0.9 x 2)
3 units: Rated current: 22.95 A (8.5 A x 0.9 x 3) / Peak current: 45.9 A (17 A x 0.9 x 3)
■ Series operation is not possible.
Load
24 V
GND
I
1
+ I
2
I
1
I
1
+ I
2
+ I
3