What is this symbol in this circuit and its functionality?

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SUMMARY

The discussion centers on the identification and functionality of circuit symbols, specifically a diode in parallel with a control relay (CR) and a capacitor with a semicircle symbol. The diode serves to protect circuits from flyback when the relay coil's magnetic field collapses. The semicircle symbol is identified as a capacitor terminating on the shield of a conductor, used to mitigate noise and voltage spikes. The conversation also touches on the use of these symbols in high voltage schematics and their relevance in data communication wiring standards.

PREREQUISITES
  • Understanding of relay circuits and their components, specifically control relays.
  • Familiarity with diode functionality and flyback protection in electrical circuits.
  • Knowledge of capacitors and their role in noise filtering and voltage spike protection.
  • Awareness of electrical schematics and standard symbols used in circuit design.
NEXT STEPS
  • Research the role of diodes in relay circuits and their flyback protection mechanisms.
  • Learn about capacitive dividers and their applications in voltage presence indicators.
  • Explore standard electrical symbols used in high voltage and data communication schematics.
  • Investigate best practices for grounding and shielding in electrical circuits to reduce noise interference.
USEFUL FOR

Electrical engineers, circuit designers, and technicians working with control panels and high voltage systems will benefit from this discussion.

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I have been working on a circuit and the manual shows a diode in parallel with "CR". I think it might either a control relay or a crystal rectifier. I am having problem building the part between +ve terminal of the 24VDC power supply and the 9 /IN POSITION terminal Can anyone please help me figure out how to achieve this circuit? This is a part of a control panel for a torch lifter system. Any input would be appreciated.
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CR is the coil for a control relay. The diode is there to protect associated circuits from flyback when the magnetic field in the relay coil falls.
 
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Averagesupernova said:
CR is the coil for a control relay. The diode is there to protect associated circuits from flyback when the magnetic field in the relay coil falls.

yes agreed and the contacts for the said relay are the ones you see just above it, the single pole double throw
 
I don't want to make a new thread because this is a really dumb question, so I will use this one. I hope it's ok.
So my question is: What kind of device is in red circle?
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It looks like a capacitor, but I don't know what that semicircle is at the end of it.
 
I am pretty sure it is showing a cap with the other end of the cap terminating on the shield of the conductor - that is why on the end near the switch there is also the Ground symbol floating in "space" Indicating the shied is grounded at the controller end, and the far end ( termination) has a capacitor to the shield to pass any noise or V spikes to the shield.
 
Windadct said:
I am pretty sure it is showing a cap with the other end of the cap terminating on the shield of the conductor - that is why on the end near the switch there is also the Ground symbol floating in "space" Indicating the shied is grounded at the controller end, and the far end ( termination) has a capacitor to the shield to pass any noise or V spikes to the shield.
I've never seen this way of expressing those standard symbols before. Interesting and makes sense. Is this a "standard" used in "data/com" or some other wiring specialty?
 
Thanks for replies. I made some additional reasearch myself and it looks like it is voltage presence indicator based on capacitive divider, which actually makes sense, because I saw the symbol mainly in height voltage schematics.
 

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