Colour light sig­nalling

Model Rail (UK) - - Workbench -

Heath­cote Elec­tron­ics makes the MAS Se­quencer and IRDASC-4 to con­trol two, three or four-as­pect colour light sig­nals solely by the move­ment of trains. The start­ing point is the MAS (Multi As­pect Sig­nal) Se­quencer. It is po­si­tioned af­ter the sig­nal so that when the front of the train reaches it, the sig­nal au­to­mat­i­cally changes to red. This repli­cates how things work on real rail­ways, where the sig­nal also changes to red as the train reaches a track cir­cuit past the sig­nal. When the en­tire train has gone past, the MAS Se­quencer’s tim­ing rou­tine be­gins. If your sig­nal has four as­pects, the red re­mains lit for a third of the tim­ing se­quence, af­ter which the yellow lights, then the dou­ble-yellow and fi­nally the sig­nal re­turns to green. The tim­ing method used by the MAS Se­quencer al­lows a two, three or four-as­pect sig­nal to be con­trolled by one de­tec­tor. Con­nect­ing power to the MAS Se­quencer is also very straight­for­ward. The IRDASC-4 is sim­i­lar to a MAS Se­quencer as it uses in­frared de­tec­tion to change its sig­nal to red. The dif­fer­ence is that rather than us­ing time, the IRDASC-4 sets its sig­nal ac­cord­ing to the set­ting of the next sig­nal up the line. For ex­am­ple, af­ter it has de­tected a train and set its sig­nal to red it will stay at red un­til the next IRDASC-4 or MAS Se­quencer up the line has both set its sig­nal to red and had the train cross its de­tec­tor. At this point it will change to yellow. The MAS se­quencer con­trols the last sig­nal on the line and an IRDASC-4 con­trols each pre­ced­ing sig­nal. A sin­gle wire links each board from the S (send) ter­mi­nal back to the R (re­ceive) ter­mi­nal. The wire be­tween these ter­mi­nals sends the sig­nal as­pect in­for­ma­tion along the line of sig­nals.

Newspapers in English

Newspapers from UK

© PressReader. All rights reserved.