You may be wondering the difference in 1/2″ and a 3/4″ bi-metal Disc besides just the size. There are are more features that change when you go up or down in size. View the Senasys line of Bi-metal Discs.
The size of the switch is actually referring to the size of the bi-metal disc used, not the size of the switch assembly. A ¾’’ switch is actually about twice the size of a ½’’ switch.
½’’ and ¾’’ switches function the same, but there are a few key differences in how they can be used.
- ½’’ switches are smaller, so they are good for applications where space is limited.
- 3/4’’ switches have more surface area on the disc, so they are slightly more accurate in sensing temperature.
- If an application requires a tighter tolerance, a ¾’’ switch would be the better option.¾’’ switches also have a higher electrical rating. For example our 430 line of ½’’ switches has a rating of 15 amps at 120 VAC, while our 2511 line of ¾’’ switches has a rating of 25 amps at 240
1/2″ and 3/4″ Bi-metal Disc Descriptions
1/2″ Bi-metal Options
The 430 Series is our 1/2″ automatic reset snap disc. These switches have a smaller footprint than the 2511 Series automatic reset thermostat switches, allowing for a lower cost. These switches are available in a single-pole, single-throw device, rated up to 15 Amps at 120VAC. The 430 snap disc thermostat switches have a temperature range of 35-350°F (2-175°C), with a differential temperature range of 15-100°F (-9-
15 AMPS – 2570/431 Series (SPST) 
These sealed thermal switches are highly versatile, carrying up to 15 Amps at 120VAC, are available SPST. The bimetal thermodisc within is set to a precise temperature range between -40°-220°F (-25°-105°C).
3/4″ Bi-metal Options
These robust thermostat switches can be used in high current applications; carrying up to 25 amps at 240VAC, for over 100,000 cycles (30 Amps at 12VDC for 30,000 cycles). These switches are available in a single-pole, single-throw device. A 3/4″ bimetal thermodisc at the heart of our thermostat is set to a precise temperature range within 0-350°F (-18-176°C).
10 AMPS – 416 SERIES (SPDT)
These sealed thermal switches are highly versatile, carrying up to 10 Amps at 120VAC, are available as a SPDT thermostat switch. The 3/4″ bimetal thermodisc within is set to a precise temperature range between -20-220°F (-25-105°C). These switches are not available to view or purchase online. Please contact us with your requirements.
Want more information on our Bi-metal Discs? Check out the links below!
Manual Reset or Automatic Reset
When to use Gold Plated Electrical Contacts
Snap Disc Quick Connect vs. Screw Terminals
