006-0007207 MPC-1250DC Guide
Rev F
32 of 44
03/03/2022
Section V
Multiple MPC Configurations
Parallel Connection of DC OUTPUTS – Parallel Option
MPC units with the regulated paralleling option can be paralleled with the proper configuration
cable. Each unit transmits its output current over the configuration cable, allowing every unit
to calculate the average output current. The units then trim their output voltage slightly in an
attempt to deliver the average output current.
Sharing is optimized when the output resistance is matched between all parallel units. The output
cables should have the same construction, similar length, and be connected at a single point.
Parallel Unit Ordering Information
Regulation Type
Example PN
Regulated Output (No Paralleling)
‑R
MPC‑1250‑1S‑1U‑L
R
28D00‑E00
Regulated Output with Paralleling
‑P
MPC‑1250‑1S‑1U‑L
P
28D00‑E00
Constant Current with Paralleling
‑C
MPC‑1250‑1S‑1U‑L
C
28D00‑E00
N+M Redundancy - Ideal Diode
The ideal diode on the DC OUTPUT provides N+M redundancy when multiple units are placed
in parallel. An N+M redundant system consists of N units to supply the maximum load, and M
additional units to provide redundancy. Typically, one additional unit is used for redundancy
giving “N+1 redundancy”.
During normal operation, all N+M units will deliver power to the load. Should one unit fail, the
remaining units will increase their output current to continue to power the load. The failed unit
can be removed and replaced to restore the redundancy level of the system to its original design.
The replacement unit can be inserted into a live, operating system, but for safety reasons it is
recommended that all units in the system be disabled first.
In addition to N+M redundancy, the ideal diode prevents power from flowing into the unit
during normal operation. This ensures that power cannot circulate between multiple units
when the outputs are in parallel. The digital communications ensures the load is shared evenly
(‑P ordering option).