2014 Q8 Relay

[asrisaku]

Hi everyone,

Could you please help review my attempt? or any suggestion?

Thanks in advance!

Best regards,
Arnut

[Peter]

I do not think that this is a good attempt.

You have described some of the very basic properties and have said in what sort of places you may find it but you have said very little about the characteristics that make it any different from the sort of relay that you can but for two pounds from Maplin or RS.

There is a clue in the question when it talks about and AC or DC railway, how has your chosen relay been made immune to traction noise?; why have you picked an operating voltage of 24v and not 2v or 500v?; what qualities do you demand from the relay contacts (current carrying, contact resistance, anti welding etc)?

You have described an ideal relay that operates exactly on 24v - what qualities do you want or can you tolerate for the pick up voltage and the hysteresis between that and the drop away?

Being really picky, you have said that your relay has 2 front and 2 back contacts. Strictly speaking your relay has 2 change over contacts (often called 2 Front/Back) since they are not independent from each other sharing the common armature.

You could also include elements like whether it is a plug in relay or fixed wiring, whether there is any coding for the plug in, issues around the security / sealing of the relay, visibility of contacts for inspection.

In the second section, you give some examples of limitation, but you have not given any appreciable explanation of the headings you have put.

Sorry to be blunt but I hope that this gives you some ideas for improvement.

Peter

[asrisaku]

Dear Peter

Thanks for making out the comments. I totally agree with you. I will try to dig more information.

Could you please point out any source of information that I can find and read it?

Thanks so much.

Best regards
Arnut

[Peter]

Dear Peter

Thanks for making out the comments. I totally agree with you. I will try to dig more information.

Could you please point out any source of information that I can find and read it?

Thanks so much.

Best regards
Arnut

You could start with the BR Specification for signalling relays. It does not tell you the WHY of the requirement, but you can probably infer the reason for the feature.

The IRSE Green Book series has one in the series called "Signalling Relays No 8" and this is available from the IRSE.

Also available from the IRSE are the green "Railway Signalling" book and the red "Railway Control Systems". They both have sections on relays.

Peter