RobinofLoxley Posted October 19, 2022 Share Posted October 19, 2022 (edited) Ive just started using a new batch of motors bought as a pack with a DR4018. I am using about 40 of these now - the turnouts Im putting the motors on are numbered 50 and up but not all numbers are in use yet. Control is via z21 and my new phone (Google Pixel 6) I have wired up three of the new batch and none operates correctly when driving the operating pin and turnout tie bar. When the clamp is loosened, operation of the slide is what I would expect, full travel which in my case is out of the box, 6mm. What actually happens is as follows - starting with the turnout set to straight in fact and showing on the layout 'mimic' 1) set turnout to divert - nothing happens (mimic now showing divert position of course) 2) set to straight - some operating noise but no movement of tie bar (motor is trying to drive against the closed position of the tie bar so it cant move, but maybe the activating pin bends a bit in situ) 3) set to divert - operates normally and completes traverse 4)set to straight - nothing happens 5) set to divert - operating noise but no motion 6) set to straight - operates normally and completes traverse In some cycles, the tie bar moves half its traverse then completes its motion on the next cycle. I am wondering if there is a fault with the DR4018 or it's set to the wrong parameters. Any ideas? Edited October 19, 2022 by RobinofLoxley Link to comment Share on other sites More sharing options...
WIMorrison Posted October 19, 2022 Share Posted October 19, 2022 What happens if you apply 12v directly to the motor? Does it operate correctly? Also have you reset the DR4018 and started from scratch with the correct parameters - only takes 5 mins (and much of that time is waiting for the kettle to boil 😆) Link to comment Share on other sites More sharing options...
RobinofLoxley Posted October 19, 2022 Author Share Posted October 19, 2022 I haven't reset the dr4018 - first job tomorrow Link to comment Share on other sites More sharing options...
KingEdwardII Posted October 20, 2022 Share Posted October 20, 2022 What turnouts are you driving? For my PECO Streamline OO turnouts, I adjust the throw distance on the MP1s to 3mm, since 6mm is too great a distance for these turnouts. It may be the case that if left at 6mm throw, the MP1s can't complete their traverse. This would explain the "noise but no motion" element. This is the kind of behaviour I get if the MP1 is mispositioned below the turnout such that it can't reach the end of of its traverse. The MP1 motors should operate correctly if operated on their own without the operating pin being connected to a turnout. Is this the case? I'm assuming you have the DR4018 set up with preset 6... You can check the output of the DR4018 with a multimeter - for each channel there should be a constant voltage between the common and one of the other pair of wires, which changes to the other of the pair when the DR4018 channel is operated. Yours, Mike Link to comment Share on other sites More sharing options...
RobinofLoxley Posted October 20, 2022 Author Share Posted October 20, 2022 (edited) I should clarify there that while there's no motion above the baseboard underneath the slider might move a bit. We've had the discussion before about setup... And I think the reset is cv47 =6 Edited October 20, 2022 by RobinofLoxley Link to comment Share on other sites More sharing options...
RMweb Gold ITG Posted October 20, 2022 RMweb Gold Share Posted October 20, 2022 I too set the traverse distance at 3mm, to avoid a similar effect that you are getting if set at 6mm. Link to comment Share on other sites More sharing options...
RobinofLoxley Posted October 21, 2022 Author Share Posted October 21, 2022 Update Last night i realised I had overlooked #49 which was the first PM on this particular Dr4018. It was working normally, but I reset the DR4018 anyway, #49 still works normally, #50-52 still behave as previously described. I put #51 on another DR4018 and it behaved as described, so something is up with the MTB's but as yet I dont know what. Im going to open one up and see what happens if I set it for 3mm travel, but really this shouldnt be a factor. Every other motor is running at 6mm. I have a mix of streamline and Hornby express and setrack points, and the Hornby points dont close 100% if 3mm is used. Link to comment Share on other sites More sharing options...
WIMorrison Posted October 21, 2022 Share Posted October 21, 2022 Are you using omega loops to pull/pull the tie rod or sufficiently flexible rod if they are underneath? I sounds very much like the motor isn’t able to throw fully. I find the supplied rod far to stiff Link to comment Share on other sites More sharing options...
RMweb Gold Harlequin Posted October 21, 2022 RMweb Gold Share Posted October 21, 2022 (edited) Are the ones that work mounted differently than the ones that don't work? Specifically, is the baseboard thickness different? The MTBs have to be able to reach the end of their travel to switch correctly and so if the throw is longer than the movement of the tie bar that extra distance has to be taken up in the bending of the needle (assuming the motor is solidly fixed). The supplied needle might not bend enough if its very close to the tiebar. So you could try inserting some packing or using a more springy needle, as @WIMorrison says. (Personally I find the supplied needles work fine with 3mm throw working Streamline turnouts through 9mm plywood.) Edited October 21, 2022 by Harlequin 1 Link to comment Share on other sites More sharing options...
RobinofLoxley Posted October 21, 2022 Author Share Posted October 21, 2022 (edited) I've not had any problems with operating any point motors up till now. I try and set them up with the slider centrally positioned so there is plenty of travel available in both directions. Most of my boards are 6mm but I mount the pm on a section of 3mm ply so I can fix screws to that - then I don't have to try and screw the motors direct to the baseboard underside. So it's equal to a 10mm baseboard I guess. I also have the pin clamps set so that vertical movement of the pin is easy - this is giving a bit of freedom to the pin and may account for them working ok with 6mm travel. I have 40 set all the same. Once or twice I had stall noises during set up but once the slider position was settled these didn't happen. The first few we're a bit of a learning process, as I tested 3mm setting but that's it. One further thing - anyone that's commented, what do you think of mtb's instructions for adjusting the throw? Edited October 21, 2022 by RobinofLoxley Addition Link to comment Share on other sites More sharing options...
KingEdwardII Posted October 23, 2022 Share Posted October 23, 2022 On 21/10/2022 at 16:01, RobinofLoxley said: what do you think of mtb's instructions for adjusting the throw? I found the instructions just fine. The real trick is using a suitable set of tweezers to grab the small pin effectively - plus doing the operation in a tray of some kind to catch the pin if it drops from your grip. Now I use tweezers that are closed in their normal position and have to be pressed to release - the sort jewellers use. These are much more suitable for this operation. Yours, Mike. 1 Link to comment Share on other sites More sharing options...
RMweb Gold Harlequin Posted October 23, 2022 RMweb Gold Share Posted October 23, 2022 On 21/10/2022 at 16:01, RobinofLoxley said: One further thing - anyone that's commented, what do you think of mtb's instructions for adjusting the throw? It all seemed straightforward to me. Link to comment Share on other sites More sharing options...
RobinofLoxley Posted October 23, 2022 Author Share Posted October 23, 2022 Well for example; to open the motor casing it has to be upside down; yet the drawing of pin position, which I don't understand, is based on the motor bring the right way up, when the cam cannot be accessed Link to comment Share on other sites More sharing options...
WIMorrison Posted October 23, 2022 Share Posted October 23, 2022 I didn’t even know that they had instructions! Have to admit that I obviously haven’t needed them 😀 1 Link to comment Share on other sites More sharing options...
KingEdwardII Posted October 24, 2022 Share Posted October 24, 2022 (edited) On 23/10/2022 at 14:56, RobinofLoxley said: to open the motor casing it has to be upside down I don't really follow your explanation at all. With the MP1, there are 2 screws in the case to remove in order to remove the slider unit which holds the rod. Once the screws are out, the slider unit can be removed to reveal the cam with its pin directly underneath. I typically do this holding the MP1 so that the slider unit is at the top all the time, easing the slider out by pushing the casing open slightly. Once the cam is exposed it is a very simply matter of extracting the pin with tweezers and moving it to the position needed for the throw distance you're trying to obtain. Then pop the slider unit back in, ensuring that the cam pin engages with the slot on the back face of the slider unit. Pop the screws back in and tighten - you're done... The only tricky bit is making sure you don't drop the cam pin, since it's on the small side and it's a pain to find if it drops to the floor. Yours, Mike. Edited October 24, 2022 by KingEdwardII Link to comment Share on other sites More sharing options...
WIMorrison Posted October 24, 2022 Share Posted October 24, 2022 3 minutes ago, KingEdwardII said: ...it's on the small side and it's a pain to find if it drops to the floor. Surely that should say Quote ...it's on the small side and it's a pain to find when it drops to the floor. 🤣 1 Link to comment Share on other sites More sharing options...
RobinofLoxley Posted October 25, 2022 Author Share Posted October 25, 2022 (edited) As I was waking up this morning still a bit dreamy I understood @Harlequin(sorry can't edit your link out it's a mistake) @KingEdwardII will try something out later today Edited October 25, 2022 by RobinofLoxley DOH! 1 Link to comment Share on other sites More sharing options...
RobinofLoxley Posted October 25, 2022 Author Share Posted October 25, 2022 As expected, the behaviour with 3mm travel is exactly the same as previously described, except with 3mm travel even less movement stake place, but the cycle is similar. I'm going to write to MTB with some advice for their instructions pages Link to comment Share on other sites More sharing options...
RobinofLoxley Posted October 30, 2022 Author Share Posted October 30, 2022 Been a bit busy, but tonight carried out a test I should have done earlier. I moved one of the 'malfunctioning' MP1's to another DR4018. It worked correctly. TBH I thought that would happen but you never know. Now I just wonder..... I have a U-shaped baseboard configuration with parallel buses from the common source which is the z21, accessories on one bus and track on the other. I am now working at the opposite side of the U from the z21 and the cable distance is about 11M to the last DR4018. Is there any chance I'm having signal integrity trouble and need to fit a snubber (or 2) to the ends of buses? My cable specs are that the buses are based on thick (at least 1mm2) solid copper, lightly twisted; cable from the dr4018's (Max 1.2M) is 3 core light duty cable, braided copper, with the exception of about 5cm at each end of thinner cable (not sure of the spec but appropriate to the connector sizes on the DR4018 and MP1's). Main cables are lightly twisted as per recs on here, DR4018 to MP1's are not. Cables run randomly, no bundling. I could run cable across the floor as a short cut, which would be about 2M but it would be lighter spec (the Dr4018 to MP1 type) as I used up all the heavy stuff on the buses. Would be a alast resort test as I would have to run both power and signal cables, quite a lot of work for uncertain aims. Link to comment Share on other sites More sharing options...
WIMorrison Posted October 30, 2022 Share Posted October 30, 2022 Get a DMM out and check the voltage that you are getting at the 'bad' MP1 input and see if it is lower than a 'good' MP1 input. If it is lower on the 'bad' MP1 input, then check the input on the 'bad' DR4018 and compare to a 'good' DR4018. I suspect that you are simply suffering a voltage drop, and you will just need to track it down. I operate my MP1 using 12v DCC to the DR4018, giving ~11v DC to the motor. All my MP1s (31) work perfectly using this arrangement. Link to comment Share on other sites More sharing options...
KingEdwardII Posted October 31, 2022 Share Posted October 31, 2022 I agree with Iain's suggestion that you check out voltages. What your description of wiring does not make clear is how you are powering the DR4018s. Do you have separate signal and power cabling to the DR4018, or are you using a single cable to provide both signal and power? A single cable might have more voltage drop over 11M since it is probably supplying multiple devices along the way - the voltage checks should show this. I have separate signal and power cables to my DR4018s - I feed 12V to the power cable. Yours, Mike. Link to comment Share on other sites More sharing options...
RobinofLoxley Posted October 31, 2022 Author Share Posted October 31, 2022 Thanks for the replies guys. Edward - I have separate power and signal cables. Iain - my problem is that I'm not very confident of my dmm - I should probably replace it - but I will check. Is it really possible to have good and bad outputs on a single DR4018? On the furthest dr4018 I have one normally functioning pm and 4 bad. Would it be a useful test to remove all locos from the track and check the PM's again? Link to comment Share on other sites More sharing options...
WIMorrison Posted October 31, 2022 Share Posted October 31, 2022 @RobinofLoxleyI thought I had replied to your post, but I can't see it 😪 Anyway, it is not that you get 'good', or 'bad' connections, I was using the terms to describe the one you have a fault with ('bad') and the others you don't have a fault with ('good'). The accuracy of the meter isn't important as we are not looking for absolute values, just relative values as a comparison of 'good' against 'bad'. Take a 'good' reference measurement of the voltage at the MP1 and compare that against the voltage for the 'bad' MP1 (you need to leave the motors connected) and see if there is a difference. If there is a difference then work back until you find that there is no difference and that will let you know where the fault lies. 1 1 Link to comment Share on other sites More sharing options...
RobinofLoxley Posted November 1, 2022 Author Share Posted November 1, 2022 (edited) I recorded about 14v on the good and random numbers on the bad. Need to measure while activating the turnout to get a value. Also found replacing the batteries helpful. I think they may have been duff when installed. On the Dr4018 where the first output worked normally the others not, testing the first output disrupted its function which was normal again once the tester was removed. Edited November 1, 2022 by RobinofLoxley Addition Link to comment Share on other sites More sharing options...
WIMorrison Posted November 1, 2022 Share Posted November 1, 2022 A DMM set to read Volts connected across the 4018 outputs should not affect the output at all. Between the centre terminal and one of the outputs for the motor should give you zero and a steady voltage when you connect to the other output. You should also be able to read the same steady voltage at the MP1 - you are sure that the 4018 is set to Preset 6? 1 Link to comment Share on other sites More sharing options...
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