3 pole SSR with Neutral connection
You left out a ton of details and have probably overlooked one of following.

SSR's are often ZCS (zero crossing switch) type so that won't work well with PID control.(that need phase controlled Triacs or missing pulse control)
you won't need PID control (anyhow) if the sensor is accurately positioned close but not too close to (/far from) the heater so as not to have a time delay with under(/overshoot. )

Just use ON/OFF control with a setpoint temperature-controlled voltage.


750W/1500W/3kW  block heaters are standard for oil or water here. (N.A.)
Why did you choose 200W x 12 = 2400W?
your thermal time constant may burn out the heater elements if dry in a few minutes, there are current sensing methods to detect this condition since the resistance rises.