Power Protection

  • Thread starter Thread starter Gert B. Frob
  • Start date Start date
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Gert B. Frob

I currently use a Cyber Power UPS. It's surge protection is rated at about
1500 joules. I note that many common power strips are rated much higher.
Is it wise to use additional surge protection and, if so, should it be
applied before or after the UPS?

TIA
 
"Gert B. Frob" said:
I currently use a Cyber Power UPS. It's surge protection is rated at about
1500 joules. I note that many common power strips are rated much higher.
Is it wise to use additional surge protection and, if so, should it be
applied before or after the UPS?

TIA

I would place it before the UPS. For example, a Tripplite
ISOBAR has a warranty that is only valid, if the power
strip is connected directly to the wall, with no other
extension cord. The power strip is probably cheaper to
replace, if the surge protection is damaged, so that
is another reason to sacrifice it first.

Paul
 
First, the reason why power strips must not be plugged into
UPS outputs: those UPS outputs deliver bad harmonics and
spikes when the UPS is in battery backup mode. So why are
these UPS outputs not destructive to the computer? Computers
are some of the most resilient appliances in the house. That
same UPS output could be destructive to some small motors and
a power strip protectors, but is just fine for a computer.

Second, the protector is not protection. The protector is
only effective when it connects a transient to protection.
Connection distance is important. Protection is earth
ground. Earthing is the only component required in every
protection system. Some systems provide protection without
protectors - ie CATV. Protected CATV wire connects less than
10 feet to earth ground before entering the building. Other
systems require a protector to connect the utility wire to
earth - ie AC electric and telephone.

But this is the point. A protector without a short
connection to earth ground is not effective. Some are
outrightly deceived into thinking a protector is protection.
It is not. The protector is only as effective as the earth
ground it connects to. No earth ground (ie too far away means
too much wire impedance) means no effective protection.

The effective protector costs about $1 per protected
appliance. It is located 'less than 10 feet' from a single
point earth ground (ie same ground required by circuit breaker
box and post 1990 National Electrical Code), and must have
sufficient joules. To be equivalent to a minimally sized
'whole house' protector, that power strip would need be 3000
joules - and cost how much per protected appliance?

'Whole house' protectors are so inexpensive and so effective
that your phone line should already have one installed for
free by the telephone company. But again, telco installed
protector also is only as effective as its earth ground. If
not connected less than 10 feet to the same earth ground as AC
electric and cable, then the protector has compromised.
Protector is only effective when it connects to protection.

AC electric is the most common source of destructive
transients. Minimally acceptable protectors are sold by
responsible retailers such as Home Depot (Intermatic) and
Lowes (Cutler Hammer and GE). Other brand names include
Square D, Erico, Leviton, Furse, GE, Polyphaser, and Siemens.
Never saw an effective protector sold in Sears, Kmart,
Staples, Walmart, Target, Office Max, or Radio Shack. A short
list of responsible manufacturers is provided.

You may need to upgrade the building earth ground to exceed
post 1990 NEC requirements. Again, protection is not the
protector nor something in a plug-in UPS. The protector is
only effective when it makes a short (less than 10 foot),
direct, and independent connection to a single point earth
ground - the protection. Ineffective protectors (ie power
strip protectors) solve this problem by pretending earthing
does not exist. Notice which type of destructive transient
they don't even discuss. Notice they claim protection only
from a transient that typically does not damage electronics to
sell their overpriced product. Ineffective protectors must
completely ignore earthing to make a sale. Ineffective
protectors typically cost tens of times more money per
protected appliance. An effective protector is as effective
as its earth ground. Earthing is the protection; not some
undersized power strip protector that hopes you never learn
what is posted above.

Above discusses your secondary protection. Its
effectiveness is defined by your building's single point earth
ground. An enhanced earth ground means adjacent protectors
are even more effective. But also inspect your primary
protection as installed by the utility:
http://www.tvtower.com/fpl.html

Notice what is the only and most critical component in a
surge protection system - earth ground. That plug-in
protector has all but no earth ground. Therefore its
manufacturer does not even discuss earthing. A protector is
only as effective as its earth ground. Start by inspecting
and upgrading the most critical protection component -
earthing.
 
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