RE: Joe Sommer/Anvilus [TANKS]

["Toast" <toast-at-shadowsofchange.com>]

You know, Joe mentioned the 2oz plating and some how my mind connected that
with a process he uses for the Anvilus controllers.  I didn't think that
this might be a piece of information he was giving Adam Klosterman because
Adam is looking at building some PCBs himself.  It does occur to me that
heavier plating on the Mini would help it stand up to that stated 150ma max
current draw for longer before giving up the magic smoke.

I thought the Anvilus Mini did proportional control.  I thought it decodes
the signal from your radio equipment and gave a 12v DC PWM output meant to
control high amp relays.  You are however telling me this isn't true?

I hope seriously that I don't have to resort to an intermediary relay
between the Mini and the heavy relay's handling motor current.

On SSR's versus automotive relays:
I'd assume there are automotive applications that do use SSRs instead of
normal spring loaded ones like the starter solenoid (which is a heavy relay)
found on most cars.   But if we are making the distinction like you are
making then I'd have to ask, if I did use just plain old spring loaded
magnetic coil type relays like they teach you about in early electronics
courses and not solid state ones, wouldn't they NOT be able to cycle fast
enough for PWM applications?  Don't they have a maximum trigger frequency
some what decided by the weight of the switch mechanism they use?  Is this
maximum frequency listed on their spec sheets?

Some of these questions I'm going to seek out and answer myself but I'm
betting that SSR's are the way to go, assuming that I can find some that
handle the current.


-----Original Message-----
From: tanks-admin-at-rctankcombat.com [mailto:tanks-admin-at-rctankcombat.com] On
Behalf Of Steve Tyng
Sent: Thursday, April 06, 2006 3:24 PM
To: tanks-at-rctankcombat.com
Subject: RE: Joe Sommer/Anvilus [TANKS]

Toast,

Since your interested in the Anvilus Mini I'm assuming you are not going
to be using proportional speed control.

If your worried if the coils from three automotive relays in parallel
will pull more than the 150ma that the Anvilus Mini driver can handle.
You can always drive an intermediate relay between the Mini and your
bank of relays.

You had a question regarding the plating on the Mini.  The only current
running through the Mini is the 5v logic current to power the onboard
electronics and the 12v current to power off-board relays.  There is no
appreciable current running through the Mini.

FYI, an SSR and what we normally refer to as an 30/40A automotive relays
are two different items.  An SSR is a Solid State Relay with no moving
parts.  The ones most often used in the hobby are the Crydom D1D40's.
SSR's can be PWM (pulse width modulated) to provide proportional speed
control.  Standard automotive relays are either on or off.

Concerning your target amperage requirements.  If your building a normal
sized model (90 to 120 pound range) I don't think you will approach
anywhere near the 120A level in normal operation.  


Steve Tyng