I just bought the NCE Power Cab and the MRC Auto Reverse Module (AD520).
Hooked up the Power Cab first. Works great.
I have a reversing loop that is gapped straight across from each other at the entry and exit. I have a main bus for the majority of the layout and a sub-bus for the reversing loop. I installed the MRC Auto Reverse Module between the main bus and the sub bus.
The Power Cab shuts down as soon at the the wheels cross the gaps. It acts exactly the same whether the MRC Auto Reverse is installed or I'm hard wire across the buses.
1) What can I do to make these work together?
2) I want to buy the NCE Smart Booster. I've heard (after I bought the Auto Reverse) that the MRC Auto Reverse does not work with the Smart Booster. Is this true? Should I just return these and get something that does work with the Smart Booster.
BTW, I've had one suggestion to stagger my gaps by about a 1/4 inch.
Thanks in advance.
Brent
The MRC autoreverser is simple and usually just works, but it is SO simple it has no adjustment for trip current. This is the problem - the PowerCab breaker trips at a lower current level than the reverser, so it drops before the reverser has a chance to function. If you want a simpel reverser that will work, try a Digitrax AR-1. Same simple hookup, just 4 wires, but the AR-1 has a knob to adjust the trip current, just adjust it til your locos can roll over the gaps even at crawl speeds and not trip the PowerCab.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Well..... I called NCE. Their suggestion was use a smaller gauge wire, but try it on a test track before ripping anything apart. So, I did and the thing worked great. So, I hooked it back up between my main bus and my reversing loop sub bus or so I thought Everything is backwards when you are looking up. I hooked it up backwards. Although, the smaller guage wire did help.
Thanks for the suggest. I felt really stupid when I figured that out. I hope it works with the Smart Booster when I get it.
SMALLER wire? What nutcase sugested that? It's not a big deal with just a PowerCab, the total power output isn't enough to do much damage, but when you add a higher current booster, smaller wire can be potentially bad for the health of your locos and decoders as it will not allow the booster to trip its circuit breaker in the event of a real short. Read the thread on Cuda Ken's MRC 8 amp booster failing the quarter test. He had a section of wire that was too thin and introduced enough resistence that a dead short did not exceed 8 amps and allow the booster to shut down as it's supposed to. Use th quarter test - set a quarter on the track at various points around your layout, the system should shut down with a short indication, WITHOUT pushing down on the quarter. This ensures that if there IS a short, from a derailment or other cause, your system will see it and shut down to protect your equipment.
This is good advice, but I can not get the Power Cab to stop tripping.
Let me describe the layout a little more.
It is a 2'x21' HO shelf layout that I've added a loop at each end to allow for continuous running. Each of the loops are about 18' long. I used 12 gauge wire for my main track bus. For each of the loops I also used 12 gauge wire for a sub bus. I installed the MRC auto reversing modules between the main track bus and each of the sub buses.
The auto reverse modules do work, but only once. When you enter the loop with matching polarity everything is good. When you exit the loop, the module flips polarity and everything is also good. If you reverse direction and go back the polarity is already matched. When you exit the loop the way your originally entered, the reverse module does not trip and the NCE Power Cab does.
I'm frustrated now. Should I change my track buses to a smaller wire? Is so, what gauge? Should I change out just the sub bus wire? Should I connect the majority of the loop to the main bus and connect the auto reverse module to a small section of the loops using the 22 gauge track feeders?
Our should I replace the modules as suggested above? Or am I doing something else stupid.
Assuming you have the modules wired correctly, it should work ok. Let me see if I follow what you said correctly: You run into the loop from the main, come around, and re-enter the main, and the reverser works fine. If you reverse the loco and go back to the loop, all is good until you get back around to the other side and try to go back out ont he main, and the reverser does not flip. Is this is what is happening? You DO have 4 total gaps in the rails, right? Both rails on the straight route through the turnout, both rails on the diverging route. What type of turnout are you using, and have you powered the frog, or is it completely isolated? That should about cover it. If they BOTH act the same way, I doubt it's a bad reverser, but if one loop works fine and the other doesn;t, try interchanging the reversers and see if the problem moves. If both do the exact same thing and all the gaps and wiring check out, the only option left is to get a different autoreverser that can operate at a lower trip current.
Randy's right. If that reverser works one way, it should work both ways. Check to make sure that your reverse section is completely isolated from the main. There shouild be no connection to your reverse loop except through the MRC autoreverser. Throw the turnout and check for continuity with the loop in both positions.
BTW, your train is shorter than the isolated reverse loop?
Martin Myers
rrinker Let me see if I follow what you said correctly: You run into the loop from the main, come around, and re-enter the main, and the reverser works fine. If you reverse the loco and go back to the loop, all is good until you get back around to the other side and try to go back out ont he main, and the reverser does not flip. Is this is what is happening?
Let me see if I follow what you said correctly: You run into the loop from the main, come around, and re-enter the main, and the reverser works fine. If you reverse the loco and go back to the loop, all is good until you get back around to the other side and try to go back out ont he main, and the reverser does not flip. Is this is what is happening?
Yes, that is exactly what happens.
rrinker You DO have 4 total gaps in the rails, right? Both rails on the straight route through the turnout, both rails on the diverging route. What type of turnout are you using, and have you powered the frog, or is it completely isolated?
You DO have 4 total gaps in the rails, right? Both rails on the straight route through the turnout, both rails on the diverging route. What type of turnout are you using, and have you powered the frog, or is it completely isolated?
Yep, 4 gaps. The only difference is the loop does not come back to the same point of the main, but I'm gapped at the entrance and exit. I'm using Atlas Code 83 turnouts.
Both loops do the same thing.
mfm37 There shouild be no connection to your reverse loop except through the MRC autoreverser. Throw the turnout and check for continuity with the loop in both positions. BTW, your train is shorter than the isolated reverse loop? Martin Myers
There shouild be no connection to your reverse loop except through the MRC autoreverser. Throw the turnout and check for continuity with the loop in both positions.
The only connection is through the autoreverser. My loop does not connect back to the main through the same turnout. I have both turnouts reversed in order to do continuous running. I'm an electrical novice (probably the reason I'm having this trouble). "Checking Continuity" That is checking the polarity?
Thanks
Have a track plan we could look at?
If you don;t have a digital meter to check voltages and so forth, if you have a Harbor Frieght near you, you can get one for $1.99 with a coupon in their latest sale flyer.
For the checkign required for the loop, all you really need is a bulb with wires, preferably one rated for 14-16 volts so it doesn't burn out on the DCC track voltage. Touch one wire to each side of the gap at one end of the loop. If the pahse matches, the bulb will not light up. If it doesn't light up, try the otehr gap at the saem location - it also should not light up, or you have a problem. Then try the other set of gaps. If it did not light up at the first set, it shoud light up at the second set, across both gaps. This would be the 'normal' operation for a reverse loop - on set of gaps dark, one set of gaps lighted. Next, take a screwdriver or othe rmetal bit, or a piece of wire, and jump across the gap at the end that DID light the bulb. The autoreverse should flip but the PowerCab stay on. Now repeat the light bulb test, both gaps that used to light up should now be dark, both gaps that were dark should now light up. Repeat The jumper wire at the now lighted gap, and you shoudl eb back to the original situation, with the bulb not lighting at the gaps yu last jumped, and lighting at the other gaps. This will verify the autoreverser is actually functioning. If this all checks out, we sort of need to see your track plan to see where the entrance and exit to the loops are, perhaps it's not the right location.