Jump to content
 

Static grass applicator damage to electronics


ozthedog
 Share

Recommended Posts

The layout I am building uses servos for point control with the control board already in place under the board.  The control board is attached to the crossmembers of the board support - not directly to the baseboard.  Track control is by DCC but this can be disconnected whilst applying static grass.  I am worried that up to 20kV of static generated by the applicator may damage the servo motors or their control board.  I have trawled a number of model railway fora to seek the opinion of others and have found much advice that SG applicators will/will not fry electronic circuitry but no-one admits to having used a SG applicator with electronics in place.  Of course I may have missed a post to this effect and will be happy to be re-directed if anyone knows of one.  I have found the German post that it can fry LEDs and also that if applied to the track can fry controllers if connected.

 

My question is - has anyone used a static grass applicator with electronics in place under the baseboard and what was the outcome?

 

Thanks

 

Keith

 

 

Link to post
Share on other sites

  • RMweb Gold

Keith,

 I have applied static grass to my baseboards with the electronics in place on the underside including servos.  However I do not switch on any of the systems such as the DCC or auxiliary power only because I do not want to short out.  Just make sure you protect the points etc. in the same manner you would as when ballast laying.

Mike

Link to post
Share on other sites

  • RMweb Premium

I have also been lucky - so far. However, there is a real possiblility of wrecking electronics, and I would always advise removing electronics before applying static grass (do as I say, not as I do). If you cannot remove the modules, then shorting the power supply wires together, and shorting the tracks, should reduce the risk of inducing high voltages in the circuits (power supplies disconnected first, of course).

Edited by Ian Morgan
Link to post
Share on other sites

  • RMweb Premium

Static damage to electronics is such that it may or may not fry the works to the extent that it stops working.  It can also cause damage which doesn't result in immediate failure, but can cause damage which results in premature failure at a later date.  (Learnt from having to sit thru' numerous ESD (Static) refresher courses at work, and being bored stiff in each and every one.....)

Link to post
Share on other sites

As an electrical blunderer who has spent the last three or more years getting my layout's wiring working at a painfully slow pace (with huge amounts of help), I've suddenly gone right off the idea of using static grass when I eventually get to that stage.

Link to post
Share on other sites

Hi,

 

Its possible to confuse human generated static with the output of an electostatic grass applicator. From reports of some of those who have touched both contacts on an applicator it may have the larger energy.

 

A former club member left a loco with sound on his layout while electrostatic grassing. It was dead afterwards. A museum fitted thousands of LEDs to a model of an airport runway. After static grassing the LEDs were dead. The Miniatur Wonderland in Hamburg remove all electronics before electrostatic grassing.

 

Some electronics has protection against human static (test may be 8kV across a 100pF capacitor). I understand some electrostatic applicators run at 20kV - I haven't found the capacitance.

 

For a club layout with lots of electronic modules I've added plug in connectors so the electronics can be removed during static grassing. I find infrared sensors are a pain to take out and put back in without losing alignment.

 

Static damage to electronics might show itself by failure at a later date.

 

 

Regards

 

Nick

Link to post
Share on other sites

  • 9 months later...
  • RMweb Gold

I have just read this thread which makes worrying reading for someone with a fleet of sound chipped locos and servo driven points and signals. Against this I feel sure that there would be a lot more negative comment around if static applicators were trashing on a regular basis.

 

I am off to research static electricity in more depth. In the meantime if anyone can explain the issue and how to mitigate in simple terms I would be grateful.

Edited by young37215
  • Like 1
  • Agree 1
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...