Compatibility of R8247 with Dapol signals

[Cowplain]

Is the R8247 compatible and able to control the Dapol signals.

[Chrissaf]

Assuming you mean the Dapol Semaphore motorised signal, then not natively.

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The Dapol signal needs a metallic momentary make contact to operate it. The R8247 outputs a voltage / current pulse. The two techniques are incompatible. You can however wire a relay to the output of the R8247 and then use the metallic relay contacts to operate the Dapol.

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This question has been asked more than once, so here is a schematic used in a previous answer.

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In this schematic, the Dapol is synchronised to the operation of a Solenoid point motor. If you just want the Dapol signal dedicated to a particular R8247 port on its own, then wire it exactly the same with the diodes, only this time omit the Solenoid point motor shown in the dotted box.

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The Dapol operates as a toggle, one pulse for danger the next pulse for clear then next for danger etc. So by wiring the interface relay to both sides of the R8247 via the diodes the relay will operate on each direction of the R8247 operation and the relay normally open 'make' contact will then toggle the Dapol.

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Any relay with a 12 volt DC coil will do as long as it has at least one normally open 'make' relay contact. This can be half a changeover with the other half normally closed contact left unused.

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The diodes are any general purpose silicon rectifier diode. For example something in the 1N4001 to 1N4006 range. The diodes prevent the Solenoid point motor coils from being 'short circuited'. If the intention is to use the R8247 port as a dedicated Dapol signal operating port without the Solenoid motor, then the diodes can be omitted, but personally I would retain them as they offer 'short circuit' protection to the R8247 port.

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If you intend to purchase a new R8247 for this project, then I suggest it might be better to purchase the Train-Tech Dapol Signal Decoder which is designed specifically for the task.

 

[Chrissaf]

Cowplain,

I have just removed your two reply attempts where you used the 'Blue Button'. Because of the images, they were delayed and held back for image approval, but were only approved and published a few minutes ago.

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Please use the appropriate 'reply method' not the 'Blue Button'. Which is to scroll down to the bottom of the page and write your reply in the 'Reply Text Box' and use the green 'Reply Button'.