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I'm installing an EV charger but my panel is only big enough to run either the dryer or the EV charger at the same time. So I have a current sensor on the dryer line so that when the dryer is running the EV charger circuit opens.

The EV charger is 240VAC, 24A, on a split phase circuit. I have a crydom SSR (rated to 50A) and heat sink but it's single pole. Is it safe for me to just break a single phase on the EV circuit when I want to disconnect the charger? (It's currently working with a standard dual pole power relay, but the panel is in my bedroom and the click on/off is really loud and keeps waking the baby).

Here is the only info I have on the EV charger circuit:

EV Charger Circuit

InternationalCodingGuru
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Instead of dealing with turning on and off the car charger you can opt for a smart EVSE with current probes that go onto the feed of the panel.

That way the EVSE can throttle charging when other loads are taking up capacity.

ratchet freak
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Ah, the things people do to charge EVs. If you actually run through your NEC 220.82 Load Calculation, you'll see that dryers come in only at 40%. EV loads come in at 125% (ask your municipality) so knocking out a dryer doesn't quite create the headroom needed to charge an EV.

However, your project would be much better served by an EVEMS system made specifically for this purpose, such as the Wallbox Pulsar Plus with Power Boost, or Emporia Load Management bundle. Trying to hork something together with electronics parts is tempting, but you will have a lot of explaining to do when it has a safety problem. This work is already done for you, and done well.

manassehkatz-Moving 2 Codidact
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Harper - Reinstate Monica
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Assuming you are also using a receptacle because it's the usual for this sort of weird DIY style charging setup, it's not particularly dangerous to break just one side of the circuit, but it's not particularly safe either. If you have one side open, the EVSE or the outlet for it can potentially appear to be dead and off due to not operating while also being live thanks to having 120V on one side. It's not an accident that equipment hooked to 240V almost always has a two pole contactor. Consider spending the $100 on a proper DPST SSR for your application.

KMJ
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