
10 Rockwell Automation Publication 1606-RM108A-EN-P - August 2020
Redundancy Power Supply —24V, 20 A, 480 W, Single Phase
Output
The output provides a SELV/PELV/ES1 rated voltage, which is galvanically
isolated from the input voltage. The output of the devices includes a
decoupling MOSFET for building 1+1 or n+1 redundant power supply systems.
The device is designed to supply any kind of loads, including capacitive and
inductive loads. If large capacitors, such as electric double layer capacitors
(EDLCs or “UltraCaps”) with a capacitance > 1 F are connected to the output,
the unit might charge the capacitor in the HiccupPLUS mode.
The device is featured with a “soft output regulation characteristic” to achieve
current share between multiple devices when they are connected in parallel.
The “soft output regulation characteristic” regulates the output voltage in such
a manner that the voltage at no load is approximately 4% higher than at
nominal load.
Attribute Value Notes
Output voltage Nom DC 24V 23.8…25.2V
Adjustment range See Adjusting the Output Voltage on page 26
Factory settings 24.1V ±0.2%, at 20 A, cold unit (results to Typ 23.9V±0.2% at
24 A and Typ 25.1V±0.2% at no load)
Line regulation Max 10 mV 85…300V AC
Load regulation Typ 1000 mV Static value, 0 A --> 20 A; see Figure 7.
Ripple and noise Max 100 mVpp 20 Hz…20 MHz, 50 Ω
Output current
Nom 24A(1)
(1) This current is also available for temperatures up to +70°C (158 °F) with a duty cycle of 10% and/ or not longer than 1 minute
every 10 minutes.
Below 45 °C (113 °F) ambient temperature, see Figure 22.
Nom 20 A At 60 °C (140 °F) ambient temperature, see Figure 22.
Nom 15 A At 70 °C (158 °F) ambient temperature, see Figure 22.
Fuse breaking(2)
(2) The fuse braking current is an enhanced transient current which helps to start heavy loads or to trip fuses on faulty output
branches. The output voltage stays above 20V. See Peak Current Capability on page 25 for additional measurements.
Typ 60 A Up to 12 ms once every 5 seconds, see Figure 9.
Overload protection Included Electronically protected against overload, no-load, and
short-circuits. In a protection event, audible noise may
occur.
Overload behavior Continuous current Output voltage >13V DC, see Figure 7.
Intermittentcurrent(3)
(3) At heavy overloads (when output voltage falls below 13V), the power supply delivers continuous output current for 2s. After
this, the output is switched off for approx. 18 s before a new start attempt is automatically performed. This cycle is
repeated as long as the overload exists. If the overload has been cleared, the device will operate normally. See Figure 8.
Output voltage <13V DC, see Figure 7.
Overload/ short-
circuit current
Max 29.8 A Continuous current, see Figure 7.
Typ 29 A Intermittent current peak value for Typ 2 s Load
impedance 10 mΩ, see Figure 8.
Discharge current of output capacitors is not included
Max 9.8 A Intermittent current average value (R.M.S.) Load
impedance 10 mΩ, see Figure 8.
Output capacitance Typ 8 000 µF Included inside the power supply
Back-feeding loads Max 35V
The unit is resistant and does not show malfunctioning
when a load feeds back voltage to the power supply. It
does not matter whether the power supply is on or off.
The absorbing energy can be calculated according to the
built-in large sized output capacitor.