sonnyyu:
Is that your standard way to speak at public forum?
No it is a special term I reserve for members who give irrelevant and wrong advice persistently despite several previous warnings.
Let's try and pick the bones out of your comments. I will assume that you are not a native English speaker so lets not dwell on things like sentence construction although it does make things hard to read.
However at practical is no go, the deal stopper is low DC power side power failure will cause high AC side is on.
A power failure on the DC side, I assume that is the LED side would not result in the AC side being on, it would result in the triac not being triggered and so no conduction would take place, the same situation as when it were off. So your comment here is just plain wrong.
if SSR is on most of time, your idea will help a lot for extend led life span.
The LED in an SSR is the most reliable component in the circuit and so the least likely to fail so extending the life span on it is not going to affect the overall performance of the component.
PLAN F
Only post when you know what you are talking about. If you are not sure on a topic and still feel you would like to contribute then acknowledge the fact in a preamble, like I am no expert but ... or I think you might ....
Remember, I have told you before, this is a beginners forum and it is incumbent upon you to give clear, accurate, relevant advice, not flights of fancy.
From the OP
Or on the other I can only turn the SSR led on from the low DC power side?
Yes that is correct.