Use one 12V 30A timer for two separate 12V inputs?
If it really is capable of switching 30A DC, then you can connect both LED strips in parallel to the 'LOAD' connection.

Looks like you want the TM630A-4 which is the 12V version, not the one in your photo which is the 250V AC version.

Looking at the datasheet for the power supply mentioned in the comments, it looks it has two separate outputs, so you won't be able to connect them both together.

The timer could be used to switch a double pole relay which could then switch the separate power supply outputs to the individual LED strips.  Or you could use the timer to power one LED strip and also control a single pole relay which switched the second power supply to the second LED strip.







simulate this circuit &ndash; Schematic created using CircuitLab

If they are totally separate supplies which the datasheet suggests, there will be a feedback mechanism on each output that keeps the output voltages constant under varying loads.  If you were to connect them together it will confuse the feedback mechanism so that one of the power supplies could end up trying to supply all the current while the other does very little.  It may cope with this, but could also cause damage.

I have just noticed that the information has this -


Which may suggest that they can be connected together, but I am not certain and I can't see anything else in the datasheet that backs this thought up.