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Chuff Chuff 29-05-2016 10:33 PM

Seep PM1 Point Motor
Hope some one can guide me on Seep Motors
I have been trying to install a seep PM1 Point Motor but hit a problem a very frustrating one, I have wired up a seep Pm1 to a peco electrofrog point but the problem is it throws one way but not the other.
It is wired up as follows: A&B To a On (Off)On momentary switch. C To 12v Dc power Supply. D to DCC Poss. E To DCC Neg. And F to the frog. And the 12 VOLT DC + to the center of the toggle switch. I have checked ensure that the throw bar has enough clearance which it seems to have. When it throws one way and I try to throw it the other way it buzzes with out moving it is very frustrating as I have another 4 to do. Any Ideas/tips will be greatly appreciated. Thankyou.

Flashbang 29-05-2016 10:36 PM

If you're 100% sure the motor or points isn't binding at all, then I would initially try increasing the power supply to 16v AC or 19 to 22 volts DC.
All wiring to and from supply to switch and motor plus the return should be 16/0.2mm equipment wire too.
Always worth trying the motor off the post in free air to see if it works both ways.

Chuff Chuff 29-05-2016 11:03 PM

Hi Flash Bang.
I am using 16/02 wire the DC supply is a Gaugemaster WM1 Power supply which can be either 12vDC or 16-23Ac. I can't see how it can bind as the hole is quite large. I have had the motor off the point and it works ok when not in the Tie-Bar

Steve M 29-05-2016 11:18 PM

The Seep should be exactly in line with the tie bar otherwise it will tighten up on one side of the throw. It also pays not to tighten the screws fixing it to the board too much to avoid any warping of the mounting.
If you have not yet cut off the pin sticking through the tie bar, remove the fixing screws and clip a small clamp or clothes peg to the pin to stop it dropping through. You can then line everything up correctly before putting the screws back.

Flashbang 30-05-2016 10:10 AM


Originally Posted by Chuff Chuff (Post 93910)
Hi Flash Bang.
I am using 16/02 wire the DC supply is a Gaugemaster WM1 Power supply which can be either 12vDC or 16-23Ac. I can't see how it can bind as the hole is quite large. I have had the motor off the point and it works ok when not in the Tie-Bar

As Steve has said, the Seep PM1 or others in that range of motors are particularly prone to not working correctly if they are fitted slightly out of alinement.
You must fit it exactly in line with the points tie bar across the point. Also ensure that when the point blades are held in the middle (two little pieces of 16./0.2mm wire work well as spacers on OO points!) the motors drive pin/slide rod is exactly centre of its travel too.

Alternatively your power supply on DC isn't quite powerful enough to overcome the mechanical movement needed to operate the point over and back. Try it on the 16v AC output. This wont hurt the Seep.

A CDU (Capacitor Discharge Unit) may also help? Only one is needed for the whole layout normally.
A CDU delivers a 'Beefy' pulse of power to the motors coil. It also gives the added advantage that should a switch be left in the On position for too long the motors coil cannot burn out, as very little current flows once the capacitor has discharged and the CDU can not recharge until all the point switches are in their Off positions. Note a CDU doesn't work too well with Hornby R044 levers but is fine with all other levers and switches.

Also worth checking... With the motor removed and by using your finger, to see if there any binding of the points moving tie bar in one direction?

Mr Bones 01-06-2016 01:55 PM

I'm new to all this, but have just wired up three (all connected to a CDU). One was doing what you describe and it turned out I had the wiring wrong so the motor only threw one way. Thankfully I did it from the point motor to a terminal block so it was easy to rectify.

Just check all the wires go where they should. Not at home now so can't check what goes where.

Flashbang 01-06-2016 02:30 PM

Seeps are quite simple to wire... One side of the supply or the CDU + positive output to the operation switches middle wiring tag, linking one switch to the next middle tags. Each switches outer wiring tags to the Seeps 'A' & 'B' connections. Seep 'C' connection to the supplies other terminal or the CDU - negative output, where a CDU is used.

Moving the switch one way applies the power to one coil. Operate the switch to the other side aplies power to the other coil.

Toggle switches must be sprung to centre off (On)-Off-(On) type, or use two press to make momentary non locking push buttons. Passing contact levers or stud and probe.

Wire throughout in at least 16/0.2mm equipment wire for reliable operation.

David A 01-06-2018 08:43 PM

Thanks for this
I just wanted to register my thanks for the expertise in this thread; it's helped me out a lot!
I thought I'd add my experience in case it helps, even if it shows my ignorance! I was getting frustrated by my point motors being seemingly unable to reliably throw the blades every time; I blamed the point motor, its alignment, then the accessory switch, then the replacement point motor of a different type. What I didn't do, until reading this thread, was check the AC output from the controller, which is 14v AC, not 16v!
From the messages in this thread I figured a CDU might do the trick, and sure enough! The point motors fire positively and firmly every time, with no buzzing from imprecise switching.
So I will use a CDU from now on, even if I don't have complex pointwork to control, and above all I will check the AC output rating from my controller!

Flashbang 01-06-2018 10:18 PM

A CDU is always worth obtaining for solenoid point motor operation.. If AC and the input is between 14 an 18 volts. Just remember that a CDU increases the AC input volts by approx. 1.4 times. Therefore for example 16V AC becomes around 22 volts output. The input current available is also important as it determines the re charge time of the CDU.
A CDU doesnt work well wiith the Hormby Black R044 lever though!

Sol 02-06-2018 06:29 AM

a story about CDU & passing contact switches

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