800V triacs may be overkill. for a 230V line . One way to specify MOV's is the max tolerance or rated line voltage of 230V and twice the Locked Rotor Current or 10A @230Vac rated operating voltage. Other considerations are power interruptions on the line.
This MOV comes in many packages from SMT to connectorized for Phoenix contacts as they have a limited number of operations for line surges but are often rated for 10kA line surges when an arc occurs across the motor or line.
Panasonic make nice leaded or thruhole Square MOV's.
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800V triacs might seem to be overkill. for a 230V line , but it is not.
AC Line surge is rated at Surge Current, 8/20µs 10,000 A thus a continuous 230Vac line at +10 tolerance or 253Vac or >253Vac , one would choose 275V and find one where 10kA is << 800V
I suggest this for your region.
The iTMOV ® varistor differs from the TMOV ® varistor by the
inclusion of a third lead for the purpose of indicating that
the MOV has been disconnected from the circuit. This lead
facilitates connection to monitoring circuitry.
LITTELFUSE TMOV20RP275M is the iTMOV type with a 3rd sense lead and has 710V @100A max from a 8/20µs lightning surge. THese $2.26 but not normally stocked. So find what is available in similar sizes.
They can be as cheap as $0.25 but remember they dont take surges forever and the above sense line is a feature.