Gaugemaster GM500 relay problem

[Clive Mortimore]

The problem is the points firing/changing but the relay is not. When taking the positive wires to the points off the relay and checking the relay with feed going to it only it works.

 

Having got fed up with being uncomfortable and bashing my head while under the baseboard I changed my thinking about powering points and the switching of the frogs.

 

The set up is as follows. The point motors are Peco PL10s directly under the points. major problem with the point motor I can lift the point. To date I have not had a problem with solenoid point motors in themselves it has always been the associated bits and bobs. 

 

Having had the Peco so called switches fall apart on me and I would need to get under the base boards they were discounted very early on. Seep motors built in switches have caused problems in the past and there is the hassle of having line them up from under the baseboard in between shouting "Ouch" because I forgot that cross member. Tortoise and the like are too expensive and again my body is not designed for confined spaces.

 

Seeing the GM500 relays I thought these would be wonderful as they can be mounted in the back of the control panel, get atable etc.

 

I am not using a switch to operate the points but the old fashioned stud contact which is a very simple form of passing contact switch. The power is directly off a Gaugemaster M1 transformer so is 16 V AC.

 

I am testing each section of track and each point as I wire them up. I had the problem of the relay not working with a single point. I took out the CDU from the circuit and it worked so did the next one. The one after is for a crossover operating two points together. Same problem, the point motors are working lovely, but the relay is not. Take the point feed off the relay and the little blighter is happy changing the polarity of the frogs. 

 

Any advice would be worth considering as I do not want to have to replace the 23 GM500s with over 30 odd switches, a bump on my head and an aching back from being in an odd sitting position.

[TheSignalEngineer]

Can you post a circuit diagram please. It will help to decide what is going on.

[Clive Mortimore]

Can you post a circuit diagram please. It will help to decide what is going on.

Hi Eric

 

 Thanks

 

I have wired it up as per the diagram from the Gaugemaster web site

 

Here is a screen print of the PDF, I have added the two resistors and three diodes to the PDF drawing that are on the PCB as supplied. I have taken the CDU out the circuit and as in the post above I am using stud contact not a passing contact switch. Other wise I have wired it up as per diagram.

[newbryford]

HI Clive.

 

It's only two.......

 

But seriously.

Have you contacted GM directly with your problem?

 

Looking at their diagrams it all seems to make sense. They only thing they note is that the positive output from the CDU is switched to terminals A&B. but as you say, it works without a point motor connected.

 

I'm guessing that your motors and GM500s are located a decent distance apart but I can't see that making a difference in this case.

 

Cheers,

Mick

[AndyID]

The problem is the points firing/changing but the relay is not. When taking the positive wires to the points off the relay and checking the relay with feed going to it only it works.

 

Having got fed up with being uncomfortable and bashing my head while under the baseboard I changed my thinking about powering points and the switching of the frogs.

 

The set up is as follows. The point motors are Peco PL10s directly under the points. major problem with the point motor I can lift the point. To date I have not had a problem with solenoid point motors in themselves it has always been the associated bits and bobs. 

 

Having had the Peco so called switches fall apart on me and I would need to get under the base boards they were discounted very early on. Seep motors built in switches have caused problems in the past and there is the hassle of having line them up from under the baseboard in between shouting "Ouch" because I forgot that cross member. Tortoise and the like are too expensive and again my body is not designed for confined spaces.

 

Seeing the GM500 relays I thought these would be wonderful as they can be mounted in the back of the control panel, get atable etc.

 

I am not using a switch to operate the points but the old fashioned stud contact which is a very simple form of passing contact switch. The power is directly off a Gaugemaster M1 transformer so is 16 V AC.

 

I am testing each section of track and each point as I wire them up. I had the problem of the relay not working with a single point. I took out the CDU from the circuit and it worked so did the next one. The one after is for a crossover operating two points together. Same problem, the point motors are working lovely, but the relay is not. Take the point feed off the relay and the little blighter is happy changing the polarity of the frogs. 

 

Any advice would be worth considering as I do not want to have to replace the 23 GM500s with over 30 odd switches, a bump on my head and an aching back from being in an odd sitting position.

 

It might be because the polarity of your CDU is reversed so that you are applying a negative pulse to the point motors rather than a positive pulse. The motors don't care about polarity but it looks like the GM500 relay does.

[Clive Mortimore]

It might be because the polarity of your CDU is reversed so that you are applying a negative pulse to the point motors rather than a positive pulse. The motors don't care about polarity but it looks like the GM500 relay does.

Thanks Andy,

 

The CDU has taken out of the circuit. The reversing of the pulse is something to explore even without the CDU.

[Clive Mortimore]

HI Clive.

 

It's only two.......

 

But seriously.

Have you contacted GM directly with your problem?

 

Looking at their diagrams it all seems to make sense. They only thing they note is that the positive output from the CDU is switched to terminals A&B. but as you say, it works without a point motor connected.

 

I'm guessing that your motors and GM500s are located a decent distance apart but I can't see that making a difference in this case.

 

Cheers,

Mick

Hi Mick

 

Thanks.

 

There were mutterings about "I should have the extra C".

 

Having worked for Gaugemaster many moons ago I know how kind the overseers are, they reluctantly do allow their minions to have Sunday evening off. I will have a chat with them today.

 

I have said the CDU is no longer being used and things are wired directly to the M1 transformer, so could AC be the problem. All  the documentation says these relays work on AC as well.

 

The problem one is a good yard away, even when all are installed there nearest relay and point motor will be 12 to 14 inches apart.

 

I am just wondering if the electrons are taking the easy way through the point motor coils bypassing the relay with the resistors blocking/restricting their route. 

[TheSignalEngineer]

The polarity of the CDU could be the problem. The relays will work on AC but need the correct polarity on DC because the diodes will block the flow.

[AndyID]

Thanks Andy,

 

The CDU has taken out of the circuit. The reversing of the pulse is something to explore even without the CDU.

 

Without a CDU it's AC so polarity has nothing to do with it. But reverting to AC can create a different problem:

 

"Just a couple of things to remember when using this - the supply is a constant AC and not a pulse as seen in CDU. This is to ensure a constant reliable power supply to both motor and the GM500. Also if you expand the picture you will notice the RESISTOR BYPASS. The GM500 has a 1K resistor built in to protect the relay coils and limit current draw on any switching devices, especially low power reed switches etc. However the power consumption of the motor(s) can starve the GM500 with the standard resistor in place, so in some situations this will need to be bypassed to allow sufficient power to operate the relay. This might not be required depending on the voltage and the internal resistance of the motors being used. For reference, we used our WM1 and GMC-PM10 motors. When bypassing the resistor you can either run a small wire link from pad to pad or attach your wire directly to the second pad as shown below."

[Clive Mortimore]

Without a CDU it's AC so polarity has nothing to do with it. But reverting to AC can create a different problem:

 

"Just a couple of things to remember when using this - the supply is a constant AC and not a pulse as seen in CDU. This is to ensure a constant reliable power supply to both motor and the GM500. Also if you expand the picture you will notice the RESISTOR BYPASS. The GM500 has a 1K resistor built in to protect the relay coils and limit current draw on any switching devices, especially low power reed switches etc. However the power consumption of the motor(s) can starve the GM500 with the standard resistor in place, so in some situations this will need to be bypassed to allow sufficient power to operate the relay. This might not be required depending on the voltage and the internal resistance of the motors being used. For reference, we used our WM1 and GMC-PM10 motors. When bypassing the resistor you can either run a small wire link from pad to pad or attach your wire directly to the second pad as shown below."

Thank you Andy

 

I will give that a try.

 

Lesson one, read all the instructions even the bits that you don't think apply to you. That is buried quite some way down amoungst drawings of applications I am not going to use it for, poor excuse.

[Clive Mortimore]

A BIG THANK YOU to every one who answered my query.

 

A special BIG THANK YOU to Andy. I bypassed the resistors on the crossover and the GM500 now works. I done the same on the next relay that switches two frogs, and will do so all of the double ones as I wire them up.

 

I ran the first train from the fiddle yard to platform one tonight. Progress.

 

Thanks everyone.

[berryr99]

Hi, just picked up on this topic out of desperation !

 

I have a similar problem. GM 500 linked to PM 1 point motors with polarity changing and motor operation via the GM 500. Power is 16 v AC. when the motors are not connected to the GM 500 the relay works fine. When the PM 1 is connected in the point motor works fine but the relay does not. I have bypassed the resistor as suggested but still have the problem with the relay not working.

 

I'm running out of ideas other than to get a couple more GM 500's and test them in case mine is faulty.

 

Just wondering if any has any further ideas that I could try

 

Thanks

 

Robert

[berryr99]

Hi, just picked up on this topic out of desperation !

 

I have a similar problem. GM 500 linked to PM 1 point motors with polarity changing and motor operation via the GM 500. Power is 16 v AC. when the motors are not connected to the GM 500 the relay works fine. When the PM 1 is connected in the point motor works fine but the relay does not. I have bypassed the resistor as suggested but still have the problem with the relay not working.

 

I'm running out of ideas other than to get a couple more GM 500's and test them in case mine is faulty.

 

Just wondering if any has any further ideas that I could try

 

Thanks

 

Robert

OK I think I have fixed the problem by using a CDU and the resistor by pass

[Patriot87003]

On 19/03/2018 at 23:11, Clive Mortimore said:

A BIG THANK YOU to every one who answered my query.

 

A special BIG THANK YOU to Andy. I bypassed the resistors on the crossover and the GM500 now works. I done the same on the next relay that switches two frogs, and will do so all of the double ones as I wire them up.

 

I ran the first train from the fiddle yard to platform one tonight. Progress.

 

Thanks everyone.

I had the same challenge last night in the shed when setting up a diode matrix using a decent CDU, decent wire thicknesses, Peco PL10s with Gaugemaster GM500 relays to switch frog polarity and LED’s for a future control panel ... and after approx 2 hours spent fault finding and testing and turning the air blue ... I gave up, searched RMWeb and found this thread ... am glad I did!

 

Yes ... it seems one PL10 works ok with a GM500, but add another and the PL10’s suck the current away from the GM500’s before enough ‘oomph’ has reached the relay ... the resistors on the GM500 act as a blocker.

 

The Gaugemaster instructions don’t appear to mention this issue (especially for this type of scenario of multiple solenoid point motors being switched at the same time). 

 

This evening I’ve tried the ‘resistor bypass’ method and pleased to report it’s worked so far, so this thread probably saved me a heart bypass!!

 

Just in case anyone else in future stumbles across the same problem ... here’s a picture of the modification I’ve progressed: simply install two ‘jump lead’ wires to bypass each resistor. I’ve chosen to install the wires on this side of the board and soldered using DCC Concepts no-clean flux to promote a quick flow to prevent melting any other joints or damaging components.

 

It’s quite a small space and fiddly job, make sure that there’s no wires touching and best to give the jump wire a little tug after soldering to ensure a firm joint.

 

 

Edited December 15, 2020 by Patriot87003
Typo/spelling!

[Iron Horse]

My God this thread is a lifeline........Thank you so much.

 

Having been out of work more times in the last 12 months than the last 35 years, when deciding to electrically operate my points I went cheapy cheap........what a mistake!!!!!!!

 

Mainly insulfrog, so the basic SEEP motor was fine to start with. Then Gaugemasters quality control seemed to go a bit awry and the operating wire started to be supplied bent so much so that it would twist around during operation and the point wouldn't fire! Anyway I digress!!!!

 

I had a couple of electrofrog points so I bought the SEEP with switch, well the bent rod and a floating washer..........well that didn't go well, so I thought how about the basic SEEP and a GM500. I have spent all day fiddling with this arrangement knowing during the testing that it was all so close and yet so far.........Thank you so much Patriot87003 your photo has saved the day.

 

Of course I have only done one, fingers crossed the solution is universal

[Patriot87003]

8 hours ago, Iron Horse said:

My God this thread is a lifeline........Thank you so much.

 

Having been out of work more times in the last 12 months than the last 35 years, when deciding to electrically operate my points I went cheapy cheap........what a mistake!!!!!!!

 

Mainly insulfrog, so the basic SEEP motor was fine to start with. Then Gaugemasters quality control seemed to go a bit awry and the operating wire started to be supplied bent so much so that it would twist around during operation and the point wouldn't fire! Anyway I digress!!!!

 

I had a couple of electrofrog points so I bought the SEEP with switch, well the bent rod and a floating washer..........well that didn't go well, so I thought how about the basic SEEP and a GM500. I have spent all day fiddling with this arrangement knowing during the testing that it was all so close and yet so far.........Thank you so much Patriot87003 your photo has saved the day.

 

Of course I have only done one, fingers crossed the solution is universal

Glad that you found this thread and hopefully the fix to add the two jumper wires will work for you as well.

 

It’s six months on from when I first stumbled across the problem and found the solution via this thread ... and I’m pleased to report that the GM500’s fitted with the jumper wires have been 100% reliable so far.

 

I’ve created a new storage yard below my layout and installed 8 turnouts at the ‘B’ end of the yard. I grouped the GM500 relays together upon a spare piece of 2” by 1” in order to wire the several common wires together in comfort away from the layout, before installing and completing the remaining wiring. The pic shows the 8 relays, along with the small jumper wires bypassing the resistors ... and again, 100% reliability so far!

 

 

Hopefully you’ll find the same across your multiple turnouts and relays ... 

[John ks]

On 16/12/2020 at 06:40, Patriot87003 said:

This evening I’ve tried the ‘resistor bypass’ method

I would be a little concerned that bypassing the resistors might reduce the life expectancy of the relay on the GM500 

I would be inclined to put a second resistor in parallel with the existing resistor

The existing resistor looks to be a 1K resistor 

A second 1k resistor in parallel would give a total resistance of 500 Ohms. if  the GM500 works reliably the  job done

 

An alternative would be to get a selection of resistors with values ranging between 100ohms & 1000ohms 

Leave the bypass in place and put a resistor in series between the yellow wire & the GM500, (two resistors, one in each yellow wire will be required)

Start with the largest value resistor & work down, in value until the GM 500 works reliably

 

John 

 

 

[KevinH]

On 19/03/2018 at 15:38, AndyID said:

 

Without a CDU it's AC so polarity has nothing to do with it. But reverting to AC can create a different problem:

 

"Just a couple of things to remember when using this - the supply is a constant AC and not a pulse as seen in CDU. This is to ensure a constant reliable power supply to both motor and the GM500. Also if you expand the picture you will notice the RESISTOR BYPASS. The GM500 has a 1K resistor built in to protect the relay coils and limit current draw on any switching devices, especially low power reed switches etc. However the power consumption of the motor(s) can starve the GM500 with the standard resistor in place, so in some situations this will need to be bypassed to allow sufficient power to operate the relay. This might not be required depending on the voltage and the internal resistance of the motors being used. For reference, we used our WM1 and GMC-PM10 motors. When bypassing the resistor you can either run a small wire link from pad to pad or attach your wire directly to the second pad as shown below."

thanks for sharing this gem - this was happening on my first attempt to use a PM2 motor and GM500 relay to power the points frog and connected diamond crossing frogs with one switch. Bypass jumpers installed and it works a treat!

[AndyID]

15 hours ago, KevinH said:

thanks for sharing this gem - this was happening on my first attempt to use a PM2 motor and GM500 relay to power the points frog and connected diamond crossing frogs with one switch. Bypass jumpers installed and it works a treat!

 

I can't remember much about it but I'm glad it helped you

 

Thanks!