Point (switch) motor power (analogue)

JimmyB

JimmyB

Semi-Retired; more time for trains.
There has been a number of threads lately about powering LGB (Piko) point motors, but I though I would start a new one. I think it is generally accepted that for a LGB point motor power (in analogue) that the recommendation is 18V ac/dc (half wave) not sure how this is written, and a number describe 18 vac through a diode to get the correct pulse. However I use a TE ancillary driver that requires 5 - 18 vdc, and after some advice was advised that a 12 vdc input would work, and throughout the summer this was fine. Now winter is here, things tighten up, damp grit gets everywhere and i have found that some of my points are no longer moving through the full throw. So hunting out a temporary 18 vdc supply, all the sticky points work fine, and am now looking for a permanent solution. 24 vdc units are widely available, but my concern is that this would damage the motor and/or the TE ancillary switch, so for the analogue electric point motor users what do you power your points from.
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
25,983
1,502
Tamworth, Staffs.
On the (indoor) layout at Chasewater:
I fitted a pair of PP3 (9v) batteries in series. These feed the points via biased, centre-off DPDT switches. - Power is only used whilst the switch is operated.
To even my surprise, the original two batteries are still going strong! 5-6 (I think) years later.

I would open up your motor's and look for debris etc. inside.. Give them a squirt of WD40 (other water-dispersing lubricants are available). give the plates/ties the blades slide on a wipe, and spray, as well.
Oh! Go round and tighten the connection screws (gently, if they need it). - You may have developed a slightly 'iffy' joint, and be losing a few volts?

Depending on your cable-run, I might think 12v is a little marginal. - Especially in the great outdoors? :think:
 
L

LGeoB

Registered
12 Dec 2017
115
21
Perth, Western Australia
Check out capacitor discharge units that are popular with many OO modeller. Basically a capacitor is charged up and then discharged through the point motor - you get a lot of energy to throw the point with little chance of burning it out. You should be okay with 24volts as the DC power supply.

Geoff
 
L

LGeoB

Registered
12 Dec 2017
115
21
Perth, Western Australia
If it just a toggle switch then probably okay - I'm not conversant with the TE.

Geoff
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
25,983
1,502
Tamworth, Staffs.
You need to go back to the 'technical' thread about this..

Christmas (and New Year) means I am unable to remember if the TE 'just' gives isolated relay contacts you can use?
AND if they are DPDT or not?

If they are just sets of contacts, then what you switch through them, is up to you, and yes, they should cope with the output of a CDU.
HOWEVER, the CDU output is a big lump of juice to throw a point. You would need a way (DPDT contacts) to invert the supply to the motor. Dependent on which way you want to throw the point.
 
JimmyB

JimmyB

Semi-Retired; more time for trains.
The TE 5474 receiver's input power, powers the receiver as well as the providing power for the output function. Having looked at the equipment again the manual says 5 - 18 vdc, however the unit itself say 5 - 16 vdc. so it would seem that 18 vdc is the maximum power input, just hoping another user could provide further user information.
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
25,983
1,502
Tamworth, Staffs.
The TE 5474 receiver's input power, powers the receiver as well as the providing power for the output function. Having looked at the equipment again the manual says 5 - 18 vdc, however the unit itself say 5 - 16 vdc. so it would seem that 18 vdc is the maximum power input, just hoping another user could provide further user information.
I think I would be looking out for a redundant laptop supply?

They are pretty robust, and designed to be 'on' for long periods. - Just need to check it gives a DC output. I would take the voltage stamped on the case (for the output) as a 'nominal' figure, and check with a meter though.. :nerd:
 
Greg Elmassian

Greg Elmassian

Registered
8 Mar 2014
3,973
563
San Diego
www.elmassian.com
Maybe helpful here to post why LGB recommended pulsed AC, basically you can hit the motor with higher voltages of pulsed AC than DC. Note the momentary switch. It's all about not overheating the motor.

I'd be careful of increasing the voltage/power unless I had exhausted every option of reducing friction.

Greg
 
Rhinochugger

Rhinochugger

Retired Oik
27 Oct 2009
27,513
1,550
North West Norfolk
Maybe helpful here to post why LGB recommended pulsed AC, basically you can hit the motor with higher voltages of pulsed AC than DC. Note the momentary switch. It's all about not overheating the motor.

I'd be careful of increasing the voltage/power unless I had exhausted every option of reducing friction.

Greg
Mmmmm - I learnt the hard way by burning out Peco 00 solenoids; since then I've gone CDU on the smaller scales indoors but it's the maintenance aspect of grit, crud and friction inducing bugs that made me go manual outside - acknowledging my intent to minimise on the shunting / switching aspects as I am an inveterate tail-chaser >:)>:)
 
JimmyB

JimmyB

Semi-Retired; more time for trains.
I have used CD on my smaller scales, and do on my 0 Gauge, but these are the "old" three wire type. 18 vdc seems to work with the TE, and is within the LGB specification, so seems I will stick (no pun intended) with that.
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
25,983
1,502
Tamworth, Staffs.
I think we are back to the fact, we have (small) real railways, in a real 'weathering' (quite often!) environment..

Infrastructure maintenance is obviously needed for trouble-free Winter running.. :):nod:
 
Rhinochugger

Rhinochugger

Retired Oik
27 Oct 2009
27,513
1,550
North West Norfolk
I think we are back to the fact, we have (small) real railways, in a real 'weathering' (quite often!) environment..

Infrastructure maintenance is obviously needed for trouble-free Winter running.. :):nod:
OK, you get the job at Network Rail :D:D
 
D

Dan

Registered
28 Jan 2010
305
25
Eastern MA
Since the 55475 TE is rated for 5-16 volts AC or DC, I have mine on my layout which is regulated DC (0 to 22 volts) or DCC (24 volts) and will work on DC as long as an engine is moving. Been working for years with no problems. One must remember that 16 volts AC when rectified is 16 times 1.414 which is 22.6 volts.
 
JimmyB

JimmyB

Semi-Retired; more time for trains.
Since the 55475 TE is rated for 5-16 volts AC or DC, I have mine on my layout which is regulated DC (0 to 22 volts) or DCC (24 volts) and will work on DC as long as an engine is moving. Been working for years with no problems. One must remember that 16 volts AC when rectified is 16 times 1.414 which is 22.6 volts.
Mine is quite clear DC, no mention of AC!