Why AVRs fail to protect Power-sensitive Equipment! M. Navid Akram Ansari Managing Director Systek (Pvt.) Ltd. February 2019

FLOW Writing on the Wall! Background Reasons Solution Features Conclusion Recommendation Outlook

‘All ICT equipment shall fail sooner than later, unless ...’ Writing on the Wall! ‘All ICT equipment shall fail sooner than later, unless ...’ (Anonymous) Not because of Murphy’s Law: ‘Anything that can go wrong will go wrong’

Writing on the Wall! AVRs JUST CANNOT PROTECT Because: Wrong equipment being used for wrong application! AVRs JUST CANNOT PROTECT POWER-SENSITIVE EQUIPMENT Period!

Background Why? Most of the ICT equipment employ SPS (Switch-mode Power Supply) The ICT equipment mostly remain ON causing SPS components to age quickly Thus they become more prone to fault on brown-out conditions The capacitor of input filter, diode of the rectifier or the switching device may fail

Background ICT Equipment Computers Hubs Gateways Bridges Routers Adapters Switches VOIP Switches Brown-out Conditions Sags Over-voltage Surges Under-voltage Spikes EMI Noise RFI

Background Nature of ICT Equipment Commonly narrow input voltage range Prone to effects of brown-out conditions Faulty SPS may pass RFI, spike or ripple to circuit Power-sensitivity increases with increase in clock-speed Require high-level of Power Quality & Reliability - PQR

Background Ensuring PQR Mains voltage stabilization Electrical noise suppression Harmonic filtrations Electrical load isolation Lightning protection Mitigation of other brownout condition

Reasons ICT Equipment get damaged because Following are deployed to protect them: Conventional Automatic Voltage Regulators (AVR) Line Conditioners incorporating such AVR These AVRs are based on one of the following: Relay Servo-motor Both these types of AVRs are ineffective in protecting ICT equipment due to their inherent shortcomings

Reasons Drawbacks of Relay-based AVR Sparking due to make and break of contacts Early failure on frequent voltage fluctuations Coarse voltage regulation due to finite tappings Slower response on higher power ratings Inability to mitigate brown-out conditions

Reasons Drawbacks of Servo-based AVR Slow response to changes in input voltage Pass on sudden sags or surges to load Gradual slowing of response over time Early failure in dusty environment Extreme output voltage upon resumption of mains power Inability to mitigate brown-out conditions

Solid-state Power-line Conditioner Solution Solid-state Power-line Conditioner Incorporating: Solid-state Electronic AVR Galvanic Isolation Additional Protection Most important is the SOLID-STATE AVR

Solution Indigenous Solution PWM SOLID-STATE POWER-LINE CONDITIONER 40 kVA 3-f OUTDOOR UNIT 40 kVA 3-f INDOOR UNIT 10 kVA 1-f INDOOR UNIT

Solution Technology Innovative Series-PWM Topology Switch-mode Technology High-frequency PWM Technology Intelligent high-frequency chopping of Series Transformer Employs IGBT modules

Solution Principle Series regulation transformer is used to control the output voltage The output voltage is controlled through the secondary by stepping up or down the input voltage at the primary The primary voltage is controlled by solid-state PWM switching of input voltage

Solution Salient Features Extremely fast response to changes in input voltage Effective mitigation of brown-out conditions Averse to dust due to solid-state parts Provides Galvanic Isolation from mains Very high efficiency High power-to-size ratio

Solid-state Power-line Conditioner Solution Parameter Solid-state Power-line Conditioner Conventional Line Conditioner Normal Stabilizer Topology Solid-state PWM Servo-control Servo / Relay-based Response Time 20 ms 400 ms ~ 600ms Accuracy ± 1.5% ± 2 - 5% ± 3 -10% Input Range 155 -280V or 110 -280V (Ext. Range) 160 - 270V 150 - 250V Surge Suppression LC, VDR, RFI VDR, RFI No Efficiency 98% 95% 90% Display Interactive LCD LCD Input/Output Volt Meter Hi/Low Voltage Protection Yes High Voltage Withstand Up to 460V Over Load Protection Software & CB CB ON Delay Selectable Remote Interface Over -temperature Protection

Conclusion Conventional AVRs (Stabilizers) cannot protect the power- sensitive ICT equipment Line Conditioners incorporating such relay or servo-based AVR cannot protect ICT equipment either Such Line Conditioners are NOT the Power-line Conditioners that are suitable for ICT equipment The only solution are the SOLID-STATE Power-line Conditioners based on Solid-state AVRs

Recommendation Deploy ONLY SOLID-STATE Power-line Conditioners to effective protect power-sensitive ICT equipment Deploy SOLID-STATE Power-line Conditioners with wide input voltage range at sites with poor power conditions Deploy SOLID-STATE Power-line Conditioners with Isolation Transformers at sites with poor earthing

Outlook Futuristic Features Event logging Input power analysis 3-f output even with 1 or 2-f outage Internet and GPRS connectivity Remote parameters monitoring Remote operation control AI for optimum performance

THANK YOU! PLEASE REMEMBER! All power-sensitive ICT equipment are BOUND TO FAIL SOONER THAN LATER! UNLESS: Protected by SOLID-STATE POWER-LINE CONDITIONER! THANK YOU!