PS2 & PS3 Track Voltage test Via DCS

Just went around with the meter and was showing a modest 18-19 volts all around the layout and at the transformer outputs....all seems well even though the engine still shows track voltage as being in the 26 volt range. The ABA Railking set also showed the same as the meter so I'm inclined to believe it is a glitch in the PS3 electronics (or something else but not a problem with transformers or power). 

Ops, sounds like something is amiss in our new PS3 land.

Probably set for European voltages

Yeah; there's probably a glitch in the programming where it's reading metric volts. 

All kidding aside, there is something wrong with the way PS3 is reading voltages. I tried my new PS3 equiped E8 and on a track powered by 16 volts, and it was reading 24. I tried a PS2 Loco and it gave readings from 15.8 to 16.4 on the same track.

However, who really uses that feature anyway? I don't really know what use it is.

Hi guys,

I'm not sure, but from the numbers you gave it sounds like the board is measuring peak to peak voltage on AC, rather than RMS voltage.  That could be a software artifact that got copied over from code developed for earlier PS3 decoders.  Until now all PS3 decoders were made for HO and only operate in DCS mode on DC current.  I'll try to remember to test an O scale PS3 engine on AC and DC next week.

Dave,

Please report your findings...I'd be interested to hear the results of your test. 

Already did the AC vs DC test at 20 volts.

The reading are the same.   The PS2's read 19.4, while the PS3 shows 27.3. 

Mike,

Interesting.  What power supply did you use for DC?

Contol Master 20  set on Mode 1(G scale) 0-20v.

AC power is a Z-4000.

The Control Master 20 uses pulse width modulation to regulate voltage, but at 20 volts it should simply be putting out 20VDC at 100% duty cycle.  That pretty well confirms that something is wrong with the math in the PS3 voltage sensor.  Out of curiosity Mike, what does the engine read if you drop the voltage to say 10 or 15 VDC with the Control Master 20?

Dave,

I tried that too. It still showed 6-7 volts higher than the power supply's output.  

It did the same on AC.  There seems to be a consistent result 6-7 volts higher than the power supply output; on AC and/or DC. 

Note that initially, all readings were taken with two PS2 and one PS3 engines stationary in the same block.  The reading was the same whether the engine was "started up" or not.   Then, with the engines moving at 6 mph, the readings were 2 (plus/minus a tenth) volts lower in all of the 3 engines.  

The PS2 engines are recent(2010)models, while the PS3 is the recent release Premier Dash-9.  All engines operate as they should with no issues. 

Dave,

I'm getting pretty much the same readings using AC with both of my PS3 engines.