power to the points

[whizzo]

Hi all , help required - all my points are lgb /epls i have never got my head round the ac bit i understand the split wave of ac - but not the volts --- i now have the proper lgb switch boxs ( 5175 ) voltage on the box is 14 v to 17 volts i have some old hammert and morgan power units of 16 v ac but the point change over is hit and miss - or just a buzz :impatient: i looked at helmsmann they do one for lgb 16v ac 5 amps i would have thought this would work ????? well8| but then i found that lgb do one which is 18volts ac 5 amp - which is a lot more money than a helmsman -- now i am :brokeheart: dont know which way to go - any help would be great regards Dave -- (also i have used 5amp twin cable to wire up the points )

 

[bobg]

Reower to the points

It sounds to me as though you are feeding AC direct to the point motors. They are actually DC.

 

[trammayo]

Reower to the points

It sounds to me as though you are feeding AC direct to the point motors. They are actually DC.

Yes, thats true - as my brother (electrician) pointed out to me. I worked mine off a 12volt battery with a momentary switch.

Mick

 

[Gizzy]

Reower to the points

Dave, you do feed the LGB switch box 5175 with AC at about 18 Volts.

However, the switches themselves have 2 diodes incorporated with their circuit and this results in half wave rectified DC, of opposite polarities.

I don't have access to a diagram of the LGB 5175 at the moment, but the AC is fed into the side and the wiring to the EPL motors is fed from the back, from what I recall....

 

[Round n Round]

Reower to the points

Hi Dave

Make sure you use a decent core size cable with as few joints as poss​

I hope this helps​

 

[whizzo]

Reower to the points

Hi all thanks for the replys - what i need to know ,but i did not make clear --is - should the system , using the 5175box work on 16 v /ac or do i need to get the lgb type at 18v ac at 5 amps sorry to be a pain regards Dave

 

[Neil Robinson]

Reower to the points

LGB used to offer a power supply specifically for point motors, signals and similar accessories, code number 51080.
This was rated at 18V ac 0.5A, not 5A.
The voltage isn't that critical and you won't need a greater current capability unless you are operating several point motors simultaneously.
As for the operation the point motors are dc, changing the point in one direction when fed with one polarity and the other direction with the opposite polarity. The polarity switchover can be obtained by using a single pole switch, two diodes and an ac supply, or a dc supply with a two pole switch.
LGB's published EPL system uses the former and the diodes are contained in the 51750 control box.

 

[Tony]

Reower to the points

Wizzy
Just to add my 10p worth LGB point motors are just that they are a little DC elec motor that runs one way then the other so any dc power will work them even the controled 12v side of you H&M transformer
Smaller scale point motors (Hornby Peco etc) (can i say the H work on here) are solyoids Eg magnet surrounded by a coil of wire so need AC power

Tony

 

[nicebutdim]

Reower to the points

Another penny to the mix; I use a Capacitor Discharge Unit and dpdt centre off switches wired as reversing switches. A CDU will switch a few motors at once, gives a short thwack of power that positively changes without damaging and only one is needed, with only extra switch required for each point. I really can't say on here just how good it really does work!
Tim

 

[ntpntpntp]

Reower to the points

Smaller scale point motors (Hornby Peco etc) (can i say the H work on here) are solyoids Eg magnet surrounded by a coil of wire so need AC power

Solenoid style point motors will work just fine on DC too - if you use a CDU in your control system (as many modellers do) that will supply DC to the coil. I built 50-odd individual CDU's for my N gauge points (Peco motors) with a view to operating several at a time via computer control at some future date (but that was in 1996 and I've still not got round to adding the computer control!) Good old push-button control panels have worked just fine!

 

[stockers]

Reower to the points

Whizzo - confused now - I would be.
PM me your address. I have some LGB leaflets here for turnouts. I'll send you one.
And a note: I wouldn't let a capacitor discharge system any where near a loco with electronics inside.

 

[nicebutdim]

Reower to the points

And a note: I wouldn't let a capacitor discharge system any where near a loco with electronics inside.

Totally agree, I'm on analogue and the point system is completely seperated from the track power. It's of no use to those who use MTS.

 

[minimans]

Reower to the points

You must feed the LGB switch box with AC current no if's or butt's! I use a 24V 5amp AC power supply for mine. the switch motors themselves are DC. Supplied rectified DC by the switch box with internal diodes.

 

[Dtsteam]

Reower to the points

You must feed the LGB switch box with AC current no if's or butt's! I use a 24V 5amp AC power supply for mine. the switch motors themselves are DC. Supplied rectified DC by the switch box with internal diodes.

[/Drift]
well done, paul - back on topic.
I use an 18vac 0.5 amp to a box that works the same way as the LGB one.
Voltage drives distance, not current, so more amps won't compensate for greater distance to the point. What more amps will do is fire more than one motor at once. 16v ought to work over a reasonable distance, and clearly it does - intermittently.

Here's my suggestions of what to check before spending money :
Does the point move freely ?
Does the point 'click'over when you put it across ?
Shift any crud around the tiebar and motor including stuff trapped in the tiebar
Lubricate the point and motor - I use wd40 but its up to you
Does the point go fully over when you push it ?
Sometimes you can displace the little rack inside the motor by one tooth - check it.
Is the motor level and flat ?
Are the wires corroded ?
Again wd40 may help
Are there any duff joints in the wiring ?
New one this one - I twisted the wires together and forgot to solder it :Looser:
Are there any kinks or shears in the wiring ?
Check as much as you can see, you'll be amazed what happens.
Are the connections to the switch box sound ?
Is anything else sharing the 16VAC power supply ?
Finally, try a different AC power supply - maybe the accessory output of an LGB controller - in case the H&M unit is a bit weary.
If you've built the LGB equivalent of Waterloo station, then ignore the above an buy a 5 amp power supply....


Best of luck