PA, PA2 Users?

[loathar]

I was looking at a PA system on E-Bay and noticed the base station had a cooling fan mounted in the top of it. I've not noticed a fan in any other pictures I've seen of these units. Is this a factory feature? I wonder if someone did a mod on this case? (it looks factory)

[Annonymous]

Do you have a link to the auction you were looking at? My PA also has a fan on top inside the plastic casing, and I bought it new from my LHS.

[Mailman56701]

  The fan is standard on MRC units.  If it comes on, it signals an overload.

[loathar]

Thanks. It must be factory then. I guess I've just never seen it from the angle in the picture.

[Tilden]

The fan is internal on the PA (at least the original ones).  The fan coming on is normal, it does not signal an overload.  The fan can come on any time to cool the CPU.  The fan will come on more often if you are drawing over two amps, i.e. running nine locos, four with sound, up grades. 

Tilden

[Mailman56701]

The fan is internal on the PA (at least the original ones).  The fan coming on is normal, it does not signal an overload.  The fan can come on any time to cool the CPU.  The fan will come on more often if you are drawing over two amps, i.e. running nine locos, four with sound, up grades. 

Tilden

  From my (original) PA manual;

 "The fan should not spin when there is no load.  If the fan turns on (spins slowly) and off perdiodically, it indicates there is an overload or short circuit."

   The consist in your example could very well be causing an overload.  From the MRR review: ".....capable of handling as many as six or seven non-sound equipped HO locomotives.
   Or the consist in your example may be causing the fan to do as you suggest.  I know what side I'd rather error on though :)

  Also this  

   Fwiw, I've *never* had it come on without an overload.
 

[Tilden]

  Mailman,

  You are refering to page 2-3 in the operations section of the original instructions, titled "Overload and Short Circuit"  This pertains specifically to a short circuit or overload beyond the rated capacity of the unit, at which point the unit is shutting itself down. 
  The preceeding paragraph "Cooling Fan" states "The cooling fan does not operate all the time.  It only comes on during heavy loads."

  I have a ramp meter on my layout.  When I'm running those multiple units, I draw 2.00 to 2.35 amps and the fan does come on and off to cool the unit.  If the fan didn't come on that would be a problem as it would likely fry the base unit.

Tilden 

[Mailman56701]

  Mailman,

  You are refering to page 2-3 in the operations section of the original instructions, titled "Overload and Short Circuit"  This pertains specifically to a short circuit or overload beyond the rated capacity of the unit, at which point the unit is shutting itself down. 
  The preceeding paragraph "Cooling Fan" states "The cooling fan does not operate all the time.  It only comes on during heavy loads."

  I have a ramp meter on my layout.  When I'm running those multiple units, I draw 2.00 to 2.35 amps and the fan does come on and off to cool the unit.  If the fan didn't come on that would be a problem as it would likely fry the base unit.

Tilden 

  No, actually, I'm referring to page 3-1, in the troubleshooting section about a dozen pages past the ones you refer too.

  However, also refering to the section you mentioned, "Overload and Short Circuit" it also states "If there is an overload or short circuit, the base unit will stop Main Track output for 2 seconds then resume; and the fan will turn on (spins slowly) and off periodically."

  So, it would appear that when the fan operates, it is doing so for one of two reasons; heavy load OR an overload/short circuit.