[GTALUG] mysterious restarts

[Lennart Sorensen]

On Tue, Jun 14, 2016 at 04:19:24PM -0400, Russell Reiter via talk wrote:
> Where does it say more amps and not more volts? I'm going by what the guys
> doing the work told me.

It says increased wire thickness.

> I mean it is possible they were wrong but it is just as possible the
> documentation you refer to is wrong.
> 
> Maybe they are going to increase voltage and current together. Line by line
> as the new equipment is deployed.
> 
> However staff did say the new cars operate on a higher voltage. They can't
> be wrong about that, it's their job to know these things.

A lot of people say voltage when they mean power or current.

The new cars need 50% more current, they still run 600V.  Without the
extra current, they can't run the A/C on them apparently.

So yes, they very much can be wrong about that.  Or at least they are
wrong in what they say about it.

Certainly increasing the gauge is to handle more current.  Voltage
increases do not require wire changes, but could need insulator changes.

So while technically possible to incrase voltage in the future, I
highly doubt it will happen.  At least in the past the subway shared
some substations with the streetcar network and hence they had to be
the same 600V, although that probably isn't being done anymore.

Still, upgrading the substations to a new voltage is not cheap and you
have the issue of how to schedule the upgrades in segments so that you
don't get different voltages connected together.

Leaving the voltage as it is, means the existing equipment can stay with
the new wires, and old trolleypoll cars can still be run on the system,
at least until the day they get rid of the intersection equipment
needed by the trolleypoles (which they appear to plan to do, to reduce
maintenance costs).

-- 
Len Sorensen