Do you really need a battery in the MTH Ps2 engines when running in Command Mode?

Paul,

While your DCS engines should operate in command (DCS) mode, be aware that if they encounter any momentary, like split-second, power dropouts (such as while traversing a dead spot on your layout), if a sufficiently-charged battery isn't present in the engine, the engine will stop and drop into conventional mode, in neutral.

Everything that you need to know about DCS is all in MTH’s “The DCS Companion 3rd Edition!" This book is available from many fine OGR advertisers and forum sponsors, or as an eBook or a printed book at MTH's web store!

Everything that you need to know about DCS WiFi is all in MTH’s “The DCS WiFi Companion 2nd Edition!" This book is available from many fine OGR advertisers and forum sponsors, as an eBook or a printed book at MTH's web store!

Have a PS-2 SD9043Mac and one day the sound dropped really low while running. At first worried it was a board, turned out the battery got low. Stores near me don't stock MTH so we replaced it with a BCR. Never tried running it without a battery. 

I think removing the batteries was a great preemptive move against damage though I'd think any battery which had been uncharged for years is a prime candidate for replacing rather than reinstalling.

No damage if running in DCS with no battery.  But it will not retain the memory changes from DCS and if you added it, it will not retain the address when you shut down.  Forcing a readd the next operating cycle.

Throw the white batteries away.  The blue 2.4AA tend to last about 7 plus years.  You could recharge them and if they hold voltage under load.  The 8.4V Batteries tend to last 4-5 years at best.  Again, charge and test.  G

Thank you all for your responses. when the time comes to setup the layout i will replace the batteries with new ones or use BCR's

Thank you again!

TESTAMONIAL: I have all bcrs in my dcs engines. Its like ron popiel says add a bcr and forget it. they cost about 20 each on the j and w websight. well worth it IMO. since getting back into dcs a few years ago and getting lots of mth engines since. not one engine has had a lick of trouble since installing the bcrs. some engines wich I have over 30 set on my shelfs for months and when they are called to duty on the layout they all say battery hi after 2 min on the track. all my engines are ps2 3volt ecept one wich is the very  first engine I ever got from mth and it was a ptoto2. got it around 2000 and its still works great. it also has a bcr installed. I do save the old batteries though. when buying used dcs engines they come in handy especially if the battery in the used engine has an issue.that way I can have one known good one untill I get a bcr for that engine. one engine I bought did not have a battery the owner must have removed it. so having a spare really helped. sorry for being long winded. just wanted to chime in and say go for the bcrs my friend you wont regret it. 

These work well for PS2 3volt, and quite a bit cheaper.