• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 32 subscribers
  • Views 1822 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Help needed with SSR circuit

John brown
Prodigy 30 points

thanks for participating and thanks for letting me ask a question (or two).

with some help of electronic relating blogs and tutorials (such as Kynix http://www.apogeeweb.net/), i'm building a kiln controller using a controller module, solid state relay(s), and thermocouple.


i built the kiln i'm controlling and it is powered by (2) 110 volt lines coming from a double pole breaker with a ground to 4 switches wired in series for 4 elements.

being new to building a control system i inquired about the parts needed.

i was told that using one solid state relay on one of the 110 lines would
cut the circuit to the kiln. i'm thinking that isn't true and that i need a relay on each 110 line with both relays connected to the same connector/actuator on the controller.

concurrently, when i inquired about adding a second breaker inline after the relay, a single pole one was recommended. again, i think not.

so... any thoughts on this matter?

i believe my kiln pulls about 28 amps. 

i have had the kiln for years. with glass kilns you need to be able hold a steady temp for 30-45 min or more at times and using 4 mechanical switches, as i have been doing, is definitely "old school".

so i researched what is needed and it appears to come to:

a digital temperature controller
a solid state relay
a thermocouple

i have purchased these items:

solo controller SL-4848-RR

solid state relay(AD-SSR640-AC-280A)

circuit breaker(WMZS1B40)

here are a couple wiring diagrams for the controller:


my understanding is that relay is a switch actuated by the controller.

i would like to add a secondary breaker close to the kiln.

i thought i would just cut the line and throw this stuff in.

the controller has a rs485 output for computers to have what is called a supervisory control and data acquisition human machine interface. scada/hmi

some interfaces can be very visually elaborate. like a web page can be.


well, that's about it in a nutshell...

thank you,

live long and prosper...

  • 0
    Prodigy 5 points

    Hello John, Thank you for posting in TI's Forum.

    110V is derived from a dual tap transformer from the AC Mains at the power pole.
    Here is a picture to describe it.




    Each 110V line is out of phase resulting in 220V  Line to Line.
    A load would be connected between the two 110V lines.
    So breaking the path to the load, your heater, only requires one switch to open the current path.

    110V in your home wiring uses one of the phases.

    Your system may be different though, and there may actually be 2 individual 110V heaters.
    You need to see how the Kiln is wired.

    The SN75107 datasheet has a few ideas for thermal control circuits.




    TI does not make the Triac shown in Figure 22, nor the transistors, thermistors, but this shows the concept.
    Figure 22 shows a heater, perhaps in a kiln, running off 220V, with the heater element connected Line to Line.
    Only one switch is required to control the current flow.

    Again you need to check the schematic of your kiln to see how the heater element(s) are wired.

    Good luck with your project.

  • 0 in reply to Ed Walker
    Prodigy 30 points
    got it! thanks a lot, Ed.
    and i will check the schematic of my kiln and let you know if i have other questions to ask. big kiss.