TECHNICAL DATASHEET
Sync DIN Rail Power Supply
24V 30W 1 Phase (NEC Class 2) / DRS-24V30W1NZ
All parameters are specified at 25°C ambient and AC input unless otherwise indicated.
www.DeltaPSU.com (July 2019, Rev. 04)
12
Operating Mode
Redundant Operation
Parallel Operation
**The Signal GND in the DRR module is for the built-in LED and DC OK signals. The Output
GND terminals from the two PSU’s do not need to be connected to the Signal GND terminal.
Fig. 3 Redundant Operation Connection Diagram
In order to ensure proper redundant operation for the
power supply units (PSUs), the output voltage difference
between the two units must be kept at 0.45~0.50V for
these 24V supplies. Follow simple steps given below to
set them up for the redundant operation:
Step 1.
Measure output voltage of PSU 1 and PSU 2. If PSU 1 is
the master unit, then V
O
of PSU 1 must be higher than
PSU 2. In order to set the output voltage, individually
connect each power supply to 50% of rated load at any
line voltage from 85-264Vac, and set the PSU 1 and PSU
2 output voltage.
Step 2.
Connect the power supply units PSU 1 and PSU 2 to Vin
1 & Vin 2, respectively, of the DRR-20N (or 20A) module
shown on the right of above diagram.
Step 3.
Connect the system load to V
out
. Please note that output
voltage V
out
from DRR module will be = V
O
(output voltage
of power supply) – V
drop
* (in DRR module).
*Vdrop will vary from 0.60V to 0.90V (Typical 0.65V) depending on the
load current and surrounding air temperature.
Fig. 4 Parallel Operation Connection Diagram
The power supply units (PSUs) can also be used for
parallel operation in order to increase the output power.
The difference in output voltage between the two units
must be kept to within 25mV of each other. This
difference must be verified with the same output load
connected independently to each unit.
Parameters such as EMI, inrush current, leakage current,
PARD, start up time will be different from those on the
datasheet, when two units are connected in parallel. The
user will need to verify that any differences will still allow
the two power supplies connected in parallel will work
properly in their product/application.
