"Mike Clarke" wrote in message
...
On 05/05/2019 13:47, Dave Plowman (News) wrote:

In article ,
Mike Clarke wrote:

[snip]

Yes, I appreciate that but I was curious why there should be different
limits for the two ends of a (symmetrical) tube.

Because the capacitance is the cable? And the ballast may not be central?

But they seem to imply that the maximum acceptable capacitance of one lead
is less than the other.

In other words, capacitances of 100pF and 200pF and lengths of 1 metre and
2 metres is fine but equal length leads of 150pF and 1.5 metres long would
not be acceptable.

Presumably the electronic ballast is more sensitive to
capacitance on those two pins than on the other two.

It isnt surprising that the ballast itself isnt symmetric with its outputs.

It's a bit of an academic point anyway, you'd be hard pushed to exceed
those length limits on a 6ft tube.