How much current must be traveling through a standard 13 amp
UK power cord to cause a fire? Put up numbers. And now how
does all that current pass through a 13 amp fuse without
blowing the fuse. Tenant was not (apparently) blowing fuses.

WE have seen fires due to power cords WITHOUT that all so
essential 15 amp circuit breaker on the power strip. Yes
there are power strips (including surge protector types) sold
without that 15 amp breaker. Shame on them. So and again,
what does the landlord want? He wants his tenants to use
power strips only with the 15 amp circuit breaker (or 13 amp
fuses) so that no overloaded wire can exist. Again because it
is not required and is so important - that 15 amp circuit
breaker on power strip (plug moles).

No blowing fuses or tripping circuit breakers. Even with
numerous items on the power cords, still the current was well
under what could be called overloading. The landlord did not
list amperages from various appliances. He just 'assumed'
multiple appliances meant overloading - an invalid conclusion.

What is the major source of fires in power cords? Not
overloading and especially not if the outlet expanders have
circuit breakers. The major source of such fires is
insulation breakdown. This is also why your Christmas tree
should be powered via an arc fault breaker. Fire due to
insulation breakdown can occur no matter how few plugs are
attached to one receptacle.

Although it will not eliminate these types of fires, the
fuse or circuit breaker would also make those fires less
possible. Fires due to overloading a wall receptacle - not
possible if the plug expander has been properly fused or
circuit breaker. Again, to make any claim of overloading,
first one must say - in detail - which wire is overloaded. No
such claim has demonstrated overloading exists. The overload
accusation is simply speculation.

Why does overloading cause fires? We still permit power
strips and other plug expanders to be sold without the
necessary 15 amp circuit breaker. Do you look at the power
strips your friends use? That was the source of a recent
local fire. But again, power strips (plug moles) did not have
that all so necessary 15 amp circuit breaker. *WE* still
don't demand that circuit breaker be on all plug expanders.
If you consider overloading to be dangerous, then you are
always looking for that 'killer'.

All above is totally and completely irrelevant to the OP's
original post. Landlord did not find a problem even though he
posts as if he did. Every power cord (apparently) was
properly fused meaning no wire could be overloaded. And yet
he still provided no information to explain damaged
electronics. He looked at things totally irrelevant -
suspected overloading, possible wrong size fuses, etc - to
explain electronic damage. False reasoning.

First, although chaining power expanders is not responsible,
still, it could not overload any wire - being as all were
fused. Furthermore, those power expanders do not explain why
the tenant suffered so much computer damage. Reasons for
electronics damage still have not been identified.
Overloading is not the reason for damage and apparently did
not exist - as demonstrated by all those 13 amp fuses that did
not blow.

Lets not forget the #1 target of this discussion. What was
damaging multiple computers and printer? Overloading did not
exist. Fuses were not blowing. And overloading would not
explain electronics damage.

"Mark D. Zacharias" wrote:
You're not totally wrong, but you're looking at things much
differently. All of us here have seen and heard where house fires
were started by overloaded outlets, especially where the person (or
tenant) did not understand about electrical current. One hundred
devices would not overload a circuit UNLESS a certain number
were actually in operation. A constant 12 amp current draw might
start a fire in a given extension cord, especially because these
type items are often manufactured substandard these days.

In the UK, each device may be limited to 13 amps, but that's no
assurance that several devices operating within their limits would
not overload a given outlet strip. One cannot absolutely trust a
circuit breaker. Fuses can be mislabeled or defeated.

Also, where there's current-flow, any contact resistance
generates HEAT. A loose plug or socket can be frying inside a wall
outlet or outlet strip, even with moderate current flow. If for
example, no one were home to see or smell it, or if a person with
disabilities could not correct the situation, one could return home
to a charred pile of rubble.

Once again, we're talking about an unknowledgeable tenant. A
friend of mine had major damage to a rental property because his
tenants were stupid this way.