Automation Canada Machine Safety Issue May 2021 - 16

CONVENTIONAL SURGE PROTECTION
VS SINGLE-ELEMENT SPDS
Why are conventional surge devices wearing out?
BY DOUGLAS PIEBIAK ME.
Power quality has been one of the hottest topics these days and surge protection is poised to be a multi-billion-dollar market within the next five years
as the US has now deemed it mandatory in all new homes. The importance of power quality is not getting dismissed like it was 10 or 15 years ago. Back
then when a building owner was trying to cut costs on their projects, SPDs (surge protection devices) were one of the first items to get cut from the
project. Nowadays SPDs are the last thing ever to get cut out of a project. Everyone is seeing how important SPDs really are and what they can do for
their business.
SPDs are relatively cost effective given that they clean up about 95% of the power problems out there. SPDs also offer catastrophic event protection
such as lightning. No other power quality device offers catastrophic event protection like SPDs. Unlike surge arrestors, SPDs are always 'active' in the
circuit cleaning the power 24/7 meaning they provide isolation of all nearby switching loads. Keeping the dirty power loads such as switching motor
loads isolated away from the digital loads. This is where users will see the best return on their investment into SPDs is when the SPDs are placed at the
downline sub-panels or at the equipment level. They say 70-80% of all dirty power comes from within our own facilities so placing SPDs on the
downline sub-panels keeps all circuits isolated, maintaining computer grade power to all circuits.
Surge protection is great at being the frontline of defence but this is not true of all SPDs. Unfortunately, some SPD manufacturers' devices will fail in
an 'open state' thus still letting the surge into their facility and leaving customers still with extensive downstream equipment losses. Any SPD
manufacturer can say how great their product is but what happens when it fails? This is what no one thinks about when they are looking into surge
protection. Am I still going to have downstream equipment loss aſter a large surge? Too oſten this is what we see with conventional 'multi-element'
SPDs in the marketplace.
Spending the time to research and look into a quality SPD is worth it. However, this task is not easy as many manufacturers try to get you to focus on
certain things to try to make themselves stand out above the others. Reading literature and looking at data specifications is one thing but now that SPDs
have been used quite heavily in the market for the last 10-years so we can now look at a company's track record. Track records don't lie and can't fool
you. Some facilities such as school boards,hospitals and universities have been dealing with high SPD failures on multiple brands. In most cases this is
where there was no large strike or anything like that, just that the lights on the SPD had randomly gone out. Why is that you might ask?
Most if not almost all SPDs in the market today use the MOV (metal oxide varistor) component to do the work inside their SPDs to clean the power.
MOVs are great for power quality; they are capable of handling high surge capacities and respond super-fast somewhere around one to five
nano-seconds depending on lead-length. What most people don't realize is that conventional SPD designs are of a 'multi-element' design.
CANADIAN AUTOMATION
VOLUME 3, ISSUE 3
16

http://www.surgepure.com

Automation Canada Machine Safety Issue May 2021

Table of Contents for the Digital Edition of Automation Canada Machine Safety Issue May 2021