AC turnout motors

[Capt. Brigg]

An article in the January 1977 MR, by Gordon Odegard, describes using a Haydon timer motor to build a "Slo-mo-shun switch motor using 2 micro switch stops for the motor power and a sp/dt switch to activate the motor. I have a box of 30 of these timer motors that specify 24VAC, 5W for 6 RPM. The timer motors are perfectly happy running on the 12VAC output from my DC throttle. I have built several of them already. A pivoting arm swings through 180 degrees until it contacts one of the two micro switches while a vertical wire pivots up through the roadbed to the points. The machine is designed for use with a SP-DT switch on a control panel, which I'm happy to incorporate. 

My question is how I can integrate these motors into my DCC system with throttle control for routing? I need a switch decoder that turns on the 12VAC and/or can switch the power from one side of the 2 input micros to the other side. Most of the decoders I have seen, like the tortoise, use track power to move the switch motor.

thanks.

[gandydancer19]

AC turnout motors are not the norm for DCC use.  As far as I know, there are no AC output stationary decoders.  It can be done if you operate a relay from the decoder, then use the that relay as a switch for the AC motors.  Not very user friendly to wire up, but workable.

But why operate your turnouts by DCC?  I know it can be done, and is nice when using a computer for automatic operations. 

Most of us have decided to use a local control panel at each switching location around the layout, just like in the DC days.  However, the control panels don't have the old DC block switches.  So when you walk around with your train, you still use the local control panel for switching, and run the trains with DCC.

[cacole]

EasyDCC stationary decoders from CVP Products of Richardson, Texas, might be what you need -- they make versions of their stationary decoder that will power heavy-duty AC switch motors.  You'll need to read through the literature to see if one of these would do what you want.

http://www.cvpusa.com/easydcc_decoders_prod_info.php 

[Capt. Brigg]

cacole

EasyDCC stationary decoders from CVP Products of Richardson, Texas, might be what you need -- they make versions of their stationary decoder that will power heavy-duty AC switch motors.  You'll need to read through the literature to see if one of these would do what you want.

http://www.cvpusa.com/easydcc_decoders_prod_info.php 

The DCC decoder does not need to supply any AC current. It only needs to pass-through a brief 12VAC low power burst to move the rotary arm off the open micro switch. The operating 12VAC will be supplied by a small 12VAC transformer and routed around the layout to all the switch motors. A secondary on-off push button at the track control panel can also be built into the system.  I want the DCC turnout decoders because I want a second train controlled by my computer while I work a local. The DCC decoders only need to provide a momentary power switch.

Cacole, thanks for the link to CVP products.

Capt. Brigg

[fwright]

Capt. Brigg

An article in the January 1977 MR, by Gordon Odegard, describes using a Haydon timer motor to build a "Slo-mo-shun switch motor using 2 micro switch stops for the motor power and a sp/dt switch to activate the motor. I have a box of 30 of these timer motors that specify 24VAC, 5W for 6 RPM. The timer motors are perfectly happy running on the 12VAC output from my DC throttle. I have built several of them already.

I suspect these timer motors will work quite happily on DC as well as AC.  Most small AC motors are universal motors that work well on AC or DC (actually more efficient on DC).  They are basically the same as the permanent magnet DC motors in our locomotives, except that a field winding is substituted for the permanent magnet.  That allows both the armature and field magnets to change polarity at the same time, allowing operation on AC.

There are synchronous motors that lock on to an AC frequency - used in the old AC wall clocks.  These motors are AC only.

Might be worth attempting to power one from the 12V DC terminals of the power pack.  If nothing happens, take the power off.  If it works, current draw should be about 200-300ma.

my thoughts, your choices

Fred W

[Capt. Brigg]

fwright

 

Might be worth attempting to power one from the 12V DC terminals of the power pack.

Fred W

Already tried that. The motors are AC only. With DC applied the rotor makes a small jump and then locks up. But, thanks anyway for the suggestion.

[Capt. Brigg]

cacole

EasyDCC stationary decoders from CVP Products of Richardson, Texas, might be what you need -- they make versions of their stationary decoder that will power heavy-duty AC switch motors.  You'll need to read through the literature to see if one of these would do what you want.

http://www.cvpusa.com/easydcc_decoders_prod_info.php 

Cacole,

I have read the web page for the EASYDCC AD4HC High Current Accessory Decoder and can't identify that they can output AC current either direct or pass through. Did you read something and identify an AC output?

[cacole]

I have installed CVP AD4 stationary decoders on a friend's layout that uses the old Kemtron twin-coil switch machines.  The decoder is connected to a separate AC (or DC) source for the power to the switch motors, and uses this power source to throw the machines.  In his case, we added a capacitor to the CVP decoder to turn it into a capacitive discharge circuit.  The actual power output of the AD4 is DC.

[rrinker]

 The timer motors are synchronous motors, they will only work on AC. Your best bet is to have a stationary decoder, just about any sort, drive a relay which would switch the AC. Since it only needs a short burts, check the decoder but most meant for twin coil motors have an adjustable 'on' time, so it the timer needs 1/2 second instead of 1/8s to get moving, you cna configure it for that. If they can work witht he contacts held, you cna just use one relay for each one and set the decoder up for continuous output, like a Tortoise. Otherwise you need 2 relays per switch motor.

 While it is often appealing to continue using things one already has, and paid money for, keep in mind these were designed before there was such a thing as a stationary decoder adn DCC, and they really aren't suitable for the types of control output options there are. You may be better of selling them to someone who doesn;t use DCC so won;t have this issue, and moving on to somethign that works without all teh extra bits added it.

 Case in point, friend's layotu I help on, he didn;t want to get rid of the old GSB and Mann-Made switch motors he had - they have the long jackscrew on the motor and slide a chunk of pcb in an aluminum channel for contacts and the moving part of the mechanism. They don;t staall, they haev cutout contacts at each end. They are also prone ot have the nut come unglued fromt eh pcb, but that's another story. The only remotely workable accessory decoder was the Lenz LS150, since it can produce a 'momentary pulse' of up to liek 3 seconds - enough time for the switch motor to fully traverse and cut itself off. So we wired a few of those in. ANd discovered the first problem - during that 3 seconds the LS150 is providing a 'pulse' it IGNORES all other switch command sent to one of its addresses. So much for using routes, or even throwing two turnouts ina  row in front of the moving train. Plus those GSB thing screech horribly - they have now almsot all been repalced with servos and controlles from Tam Valley. Other turnouts have Tortoises, those are staying, bt the LS150s have been repalced by DS64s and the pushbuttons rewired to trigger the DS64 instead of power the Tortoise directly.

                              --Randy