How to parse 「場合でも」


I was standing at a urinal recently as tried to read the note on the top
surface. It was as follows:

> 人がいない場合でも水が流れることがあります

Based (mostly) on the words and context I would expect this to mean something
like "When there is no person, there will be a flush of water"

I am hung up on the [場合でも」 part. In [this
question](https://japanese.stackexchange.com/questions/54458/is-%E5%A0%B4%E5%90%88%E3%81%AF-
considered-a-conditional-form-and-how-do-you-correctly-use-it) [場合」 is
explained as typically being followed by に and/or は. Both of those make sense
to me as a typical particle usage for a "temporal noun", but I am not sure
what the 「でも」 usage is.

How is 「でも」acting here, or is it 「で＋も」? Thank you!




I would structurally translate this as:

> 人がいない場合でも水が流れることがあります。
>
> There are times when the water will flow, even if it is the case where there
> is nobody (here).

The N+でも construction expresses the same as Vて+も, なadj+でも いadj＋くても, which
indicates a 'reverse condition', usually translated to "even if" - i.e.
explaining a scenario which is contrary to what you might think. Usually, I
suppose, a urinal's flushing feature only activates after use, by using one of
those infra-red sensors; this is simply explaining that they may also
(surprisingly) activate as a matter of course, without a person needing to use
it/be there to trigger it.

場合 is often used in a related way, in "no matter the case" type phrases, with
どんな・どの場合でも:

> どんな場合でも私は笑っていた。No matter the situation (case), I was smiling.
>
> この規則はどの場合でも当てはまる。This rule applies in all cases.
>
> どんな場合でも皮膚の色で人を判断すべきではない。 (Whatever the case) you should never judge people
> by the colour of their skin.




I would structurally translate this as:

> 人がいない場合でも水が流れることがあります。
>
> There are times when the water will flow, even if it is the case where there
> is nobody (here).

The N+でも construction expresses the same as Vて+も, なadj+でも いadj＋くても, which
indicates a 'reverse condition', usually translated to "even if" - i.e.
explaining a scenario which is contrary to what you might think. Usually, I
suppose, a urinal's flushing feature only activates after use, by using one of
those infra-red sensors; this is simply explaining that they may also
(surprisingly) activate as a matter of course, without a person needing to use
it/be there to trigger it.

場合 is often used in a related way, in "no matter the case" type phrases, with
どんな・どの場合でも:

> どんな場合でも私は笑っていた。No matter the situation (case), I was smiling.
>
> この規則はどの場合でも当てはまる。This rule applies in all cases.
>
> どんな場合でも皮膚の色で人を判断すべきではない。 (Whatever the case) you should never judge people
> by the colour of their skin.

