@doug293cz , thank you so much for looking at my design. I have looked at some of your reference designs and took inspiration for mine. If you don't mind, would please indulge me some questions and responses to your advice?
1. Neutrals do not need to be switched
The switches I have are 250v 30A illuminated DPST which require the neutral or second hot leg to light the bulb. Based on this, am I wrong on what I have sketched?
You show the neutral passing thru the switch to the load, so the diagram is confusing.
2. Black hot phase and neutral should not connect to the float/no float switch selector switch
The selector switch is illuminated, so it needs the hot/neutral or hot1/hot2 connected to the lighting block to light the lamp.
To do what you are proposing the switch would need four NO contact blocks, plus the lamp block. You need separate contacts for the low voltage controls signals to the SSR, and the line voltage for the lamp. Also, how will the lamp logic work? On for only one of the On switch positions, or On for both On switch positions? If On for both, how do you know from the light which mode is enabled?
3. The element firing indicator lamp should connect to the red hot phase rather than neutral
Is that due to what
@BAF was saying about needing a 240v indicator lamp for the element?
Yes
4. You should consider adding an element enable switch and contactor so that you can shut off the element in the event of SSR latching or total failure (should be a lighted switch)
My float/no float switch is also an element enable/disable switch by switching the positive DC control lead to the SSR. I know this does not address SSR malfunction/failure, but it seems to be a good initial control mechanism. The contactor I have in the system switches the hot out to the SSR and the always on leg to the element outlet utilizing a lighted switch. Is my presumption that this would do what you are prescribing inaccurate?
No, as you have to shut off the entire system to isolate a failing (not responding to control signals) SSR. Switching control signals does nothing to shut down this failure mode. @Bobby_M
gives some good advice about changing the contactor to only control the element power, rather than all power. It addresses the ability to shut off a failing SSR, while not shutting down the whole system. You don't really need to control power to the low power devices with a contactor, or even a switch if the panel can be unplugged from the power source (all your devices internal to the panel draw much less than 1A total.) It's useful to have the DSPR power come on before the element power is enabled, as the DSPR will try to turn on the SSR/element if it was not left in the correct state at the end of the previous run. I prefer designs with a main power contactor, and element enable contactors, as they allow the implementation of a "Safe Start" interlock. The interlock prevents main power from being turned on if any pump or element switches are on. Prevents unexpected behavior on power up.
Thank you again, I really appreciate your advice and assistance.