Download Redundant vs. UPS

DC P
Pow
wer SSupp
pliess
Redundan
nt vs. UPS
How to Ch
H
hoose the Right Onee
 Redundant – Keeps the system
m operatingg when a po
ower supplyy fails  UPS – Pro
otects again
nst power o
outages ww
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A
Application Brrief How
w to C
Choosse thee Rigght Power Su
upplyy Solu
ution
Introduction Reddundant Pow
wer Supply Syystems Both a Redu
undant Powerr supply systeem and a DC A reedundant pow
wer supply sysstem consistss of two UPS (uninterrruptable Pow
wer Supply) syystem serve (or m
more) similarrly sized AC ‐ D
DC power sup
pplies a purpose in
n an industriall control paneel. If the instaalled along w
with a diode syystem that preevents 24VDC powe
er supply failss, a UPS does not help; a feeddback to connnected powerr supplies. Th
his redundant p
power supply continues to operate. systtem is wired inn a way to allow both pow
wer When the po
ower goes do
own, a redund
dant power suppplies to providde DC voltagee to the samee load. supply does nothing; but a UPS allows time to take (Figuure 1) The Om
mron Redundancy Units S8
8VK‐R10 action. Understanding eaach system will help make and S8VK‐R20 coontain the Dio
ode system an
nd a n different a choice as tto the best system to use in
deteection circuit to monitor th
he status of both applications. pow
wer supplies. Figure 1 Om
mron’s Redund
dant Power Su
upplies DC Power Sup
pplies: Redun
ndant Power SSupply vs. UPS D
2
A
Application Brrief The Redundancy unit is designed to prroperly is 500mV or less. By adjusting tthe input volttage between the ttwo power balance the output load b
untiil the LED is O
ON the outputt current of each ectively using each power ssupply. supplies effe
pow
wer supply will be balanced
d. By balanciing the When the po
ower suppliess are correctlyy sized this loadd the operatinng life of each
h power supply will extend tthe life of each power supp
ply by sho uld be more tthan twice wh
hen compared to drawing halff the load current from eacch power usinng only one poower supply. supply. The Redundant un
nit is also in p
place to mplete current load from properly transfer the com
one power ssupply to the other if one sshould fail. The Omron redundancy u
units (S8VK‐R1
10 and dancy monitorr system S8VK‐R20) have a redund
that includess a redundanccy operating LED, voltage balance LED and a signal output for faiilure of a undancy operaating LED power supplly. The redu
will turn ON when the inp
put voltage difference is ower supply 2.4V or less. The led will tturn off if a po
nnection error causes one power fails or a con
supply not to
o provide volttage. The voltage balance LED indicates when the voltagge difference
DC Uninterruptable Power SSupply (UPS)) Systtems Thee DC UPS systeem consists o
of an AC‐DC po
ower sup ply; UPS conttrol unit and aa lead acid battery. help provide p
power (Fig ure 2) Thesee 3 parts can h
up tto 40A for 30 minutes. This system will con tinue to operrate when theere is a powerr outage but may not provvide power if one of the 3 parts m will operate until the com
mputers failss. The system
can proper save and safely shutdown the PS equuipment. The proper sizingg of the DC UP
Chaarging unit andd the battery size is requirred and cou ld increase thhe cost of thee complete sysstem. Figure 2 Uniinterruptible Power Supplyy (UPS) DC Power Sup
pplies: Redun
ndant Power SSupply vs. UPS D
3
A
Application Brrief The UPS systtem will require weekly an
nd monthly If thhe system hass a critical memory compon
nent or maintenance
e to make surre the system is operating musst finish a process during a power outagge then properly. Just like a Monthly test of a battery a DC
C UPS system should be ussed. The UPS system operated exit light system
m the UPS system should will keep the com
mputers up an
nd running un
ntil a he battery is ccharged and be tested to make sure th
propper save operration and saffe shut down mode the UPS control unit is properly directing power to can be reached. The cost will increase with
h the the load. amoount of equipment requirin
ng power from
m the UPSS battery. When to Usse Each Type
e The two systems, redundant p
power suppliees and The Redundant power supply system is a cost effective way for industrial application
ns like food & beverage paackaging, material handlingg or conveyors to
o always operrate during standard hours of manufacturing. In most automated UPS do not offfer a solution
n to the samee DC U
induustrial manufaacturing prob
blem. Carefully chooosing the correct solution can keep the mannufacturing up and runningg and save mo
oney at the same time. manufacturing and distrib
bution facilitiees if the complete plaant power goes out then the operators cannot workk. A redundan
nt system helps eliminate any down tim
me due to component failu
ure. DC Power Sup
pplies: Redun
ndant Power SSupply vs. UPS D
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T35I‐E‐01 Notte: Specifications aare subject to chan
nge
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