On Wed, 25 Apr 2018 00:55:04 +0100, Cursitor Doom wrote:

On Tue, 24 Apr 2018 21:57:46 +0100, Jimmy Wilkinson Knife wrote:

They are pretty **** actually. I had a kettle running at 2400W (10
amps) on a 5A plug fuse which lasted for 3 months of using it several
times a day before it blew. And a colleague had 2 tumble driers and 2
washing machines running on a 4 way power strip, which melted the strip
into a soggy mess and didn't blow the 13A fuse. Makes you wonder why we
have them at all. Surely they can design them to take triple load for 5
seconds (to allow for motors starting), then blow if it's over the
rating after that? Simply the temperature of the wire should reach a
certain point? But all we seem to have is "fast blow" which won't allow
for motors and "slow blow" which is in plug fuses and doesn't blow other
than a dead short.

I'm inclined to agree. Hardly anyone other than sparkies is aware that
any given mains fuse will pass a great deal more than its rated value for
a surprisingly long time during which much melting or even a fire could
possibly start. Such fuses are great for protecting against dead shorts,
but not much beyond that.

You can buy fast blow fuses which are very good at protecting, but are no good for motors starting. Surely a compromise could have been made?

Fuses don't protect people plugging too much in (unless you nicely overrate the cable - my garage has a 30A cable with a 15A fuse, and the fuse will blow before the cable melts), but they do stop things happening like dodgy halogen spotlight bulbs shorting out. However they don't blow quick enough to protect transistors in PIR light switches, which is why I fitted circuit breakers for the lighting (that is until I put the lighting circuit on a UPS to make the LED bulbs last longer - the mains supply is **** and full of surges, brownouts, and terribly low and high voltages.)

--
Here are some actual maintenance complaints/problems, generally known as squawks, recently submitted by QANTAS Pilots to maintenance engineers. After attending to the squawks, maintenance crews are required to log the details of the action taken to solve the pilots' squawks.

Problem - Left inside main tyre almost needs replacement.
Solution - Almost replaced left inside main tyre.

Problem - Test flight OK, except autoland very rough.
Solution - Autoland not installed on this aircraft.

Problem - No. 2 propeller seeping prop fluid.
Solution - No. 2 propeller seepage normal. Nos. 1, 3 and 4 propellers lack normal seepage.

Problem - Something loose in cockpit.
Solution - Something tightened in cockpit.

Problem - Dead bugs on windshield.
Solution - Live bugs on backorder.

Problem - Autopilot in altitude-hold mode produces a 200-fpm descent.
Solution - Cannot reproduce problem on ground.

Problem - Evidence of leak on right main landing gear.
Solution - Evidence removed.

Problem - DME volume unbelievably loud.
Solution - Volume set to more believable level.

Problem - Friction locks cause throttle levers to stick.
Solution - That's what they are there for!

Problem - IFF inoperative.
Solution - IFF always inoperative in OFF mode.

Problem - Suspected crack in windscreen.
Solution - Suspect you're right.

Problem - Number 3 engine missing.
Solution - Engine found on right wing after brief search.

Problem - Aircraft handles funny.
Solution - Aircraft warned to "Straighten up, Fly Right, and Be Serious."

Problem - Target radar hums.
Solution - Reprogrammed target radar with words.

Problem - Mouse in cockpit.
Solution - Cat installed.

Defect: Seat cushion in 13F smells rotten.
Action: Fresh seat cushion on order.

Defect: Turn & slip indicator ball stuck in center during turns.
Action: Congratulations. You just made your first coordinated turn!

Defect: Whining sound heard on engine shutdown.
Action: Pilot removed from aircraft.

Defect: Pilot's clock inoperative.
Action: Wound clock.

Defect: Autopilot tends to drop a wing when fuel imbalance reaches 500 pounds.
Action: Flight manual limits maximum fuel imbalance to 300 pounds.

Defect: #2 ADF needle runs wild.
Action: Caught and tamed #2 ADF needle.

Defect: Unfamiliar noise coming from #2 engine.
Action: Engine run for four hours. Noise now familiar.

Defect: Noise coming from #2 engine. Sounds like man with little hammer.
Action: Took little hammer away from man in #2 engine.

Defect: Whining noise coming from #2 engine compartment.
Action: Returned little hammer to man in #2 engine.

Defect: Flight attendant cold at altitude.
Action: Ground checks OK.

Defect: 3 roaches in cabin.
Action: 1 roach killed, 1 wounded, 1 got away.

Defect: Weather radar went ape!
Action: Opened radar, let out ape, cleaned up mess!