Sonoff 5V controlling external 5V NC relay for door phone gate control

I’ve been wanting to control access to my front gate through my door phone using a Sonoff for quite a while, the issue is that you need a NC relay not NO and the Sonoffs are largely NO relays.

What I’ve done and seems to be working is the following…

I’ve flashed a Sonoff RE5V1C with Tasmota and set pulsetime1 20 (which turns on the relay for 20ms and then back off)

I’ve then taken an external 5VDC relay that I had and wired it so that it receives voltage when the Sonoff is toggled, the 5V relay I have has both NO and NC, I’ve connected a diode between the input terminals on the coil to protect it.

Voltage from the door phone is around 5.65VDC so I’m powering the Sonoff directly from the door phone.

Is it OK to power an external relay through another relay or can I expect to have issues with this down the line? Don’t exactly want to have to have my gate open because of an over sight :slight_smile:

Some images below of my wiring of the relays.

Perfectly fine.