Re: D1D40 SSR's burning out?? [TANKS]

["flier" <FLIER-at-sbcglobal.net>]

Grant,

Have you measured your max current draw?


--- Original Message ---
From: Grant Mahalek <gmahalek-at-shaw.ca>
To: tanks-at-rctankcombat.com
Subject: Re: D1D40 SSR's burning out?? [TANKS]

>Hi Norm,
>
>In Test #1 the right SSR got very hot.
>
>I forgot to check the SSR temperatures in Test#2.
>
>Grant
>  ----- Original Message -----=20
>  From: Norman Wieser=20
>  To: tanks-at-rctankcombat.com=20
>  Sent: Tuesday, November 01, 2005 9:08 PM
>  Subject: Re: D1D40 SSR's burning out?? [TANKS]
>
>
>  Hi Grant
>
>   Did the SSR's get very Hot ?
>
>  Norm
>    ----- Original Message -----=20
>    From: Grant Mahalek=20
>    To: tanks-at-rctankcombat.com=20
>    Sent: Tuesday, November 01, 2005 6:27 PM
>    Subject: Fw: D1D40 SSR's burning out?? [TANKS]
>
>
>    Hi there,
>
>    I've run into a bit of a problem in the 
construction of my Hetzer.  =
>I've burned out three Crydom SSR's with my Anvilus 
proportional motor =
>controller.  I've sent off an email to 
www.crydom.com today in hopes of =
>getting some suggestions.  The Crydom website 
mentions something called =
>"Transient Protection" and protection of the SSR's 
using fast recovery =
>type diodes with PIV rated greater than supply =
>voltage(....cool....unfortunately I don't completely 
understand this). =
>Has anyone out there
>
>    In the "Tri-Pact News Service" article 
entitled "R/C Combat Vehicles =
>Speed Controls" under the section "Other Issues" 
various devices are =
>recommended to limit power surges and radio 
interference.  After a small =
>fix(installation of a CMOS NAND 4011 Gate) into the 
steering and =
>throttle servo leads, radio interference is no 
longer a problem.
>
>    However, burning out these SSR's is becoming a 
bit of a =
>pain....xxo!!/?##.
>
>    Can anyone out there offer suggestions, detailed 
or otherwise on how =
>to overcome this obstacle?  Any suggestions would be 
much appreciated.
>
>    Oh, by the way, the rubber boat roller drive 
wheels did not work, =
>the rubber was too hard and the drive wheels slipped 
in the tracks.  =
>I'am going to use the "tried and true" TTS rubber 
bungee cord wrapped =
>plywood drive wheels.  And for those of you 
wondering about what =
>thickness of drive-shaft to use, I support Steve 
Tyng's suggestion to =
>use a hardened steel shaft > 1/2 inch.  I've already 
bent both my 1/2 =
>inch drive shafts in the minimal testing I've done 
so far.
>
>    Supper call....thanks for any help you guys can 
offer.
>
>
>    Grant P. Mahalek
>
>    ----- Original Message -----=20
>    From: Grant Mahalek=20
>    To: support-at-crydom.com=20
>    Sent: Tuesday, November 01, 2005 7:33 AM
>    Subject: D1D40 SSR's burning out??
>
>
>    Hello there,
>
>
>    I'am a hobbyist using a pair of Crydom D1D40 
SSR's with a motor =
>controller to provide proportional speed control for 
a custom built 1:6 =
>scale radio control combat tank. The motor controller
(Anvilus RC Relay =
>SSR Motor Controller; Board h_050412, Manual 050425) 
is described in =
>detail at www.anvilus.com . The motor and control 
system is wired =
>according to figure 3, page 5 of the manual.  I'am 
using a pair of new =
>electric scooter motors(MY1016) from 
www.unitemotor.com operated at =
>24Vdc. Motor specifications: 24Vdc, 2750 rpm, 
15.4amps, 280watts. There =
>is a 40 amp automotive fuse installed in-line on the 
each motor power =
>lead.  No other circuit protection is provided.
>
>    I have burned out three(3) Crydom D1D40 SSR's 
thus far.  This is =
>getting a little expensive for a hobby......
>
>    Can you help?
>
>    Circumstances of failures:
>
>    1.)Test #1; left SSR failed; left SSR -1 
terminal wires became loose =
>during tank test run. Up to this time(20 minutes of 
run time), the =
>electronics and drive system were operating with 
full mixing and =
>proportional speed control.  Right drive motor and 
right SSR became very =
>hot.
>
>    2.)Test #2; right SSR failed after about 20 
minutes of fully =
>proportional run-time. No apparent loose electrical 
connections. No =
>apparent mechanical binding in drive-train. Right 
drive motor became =
>very hot.
>
>    Apparently, there are twenty to thirty RC combat 
tanks using the =
>same electronics(with Crydom SSR's) and drive 
systems with almost =
>identical components with no problems.
>
>    Do you have any suggestions regarding the 
inclusion of circuits or =
>components to protect the SSR's from being burned 
out.  Could you please =
>be very specific with any suggestions regarding 
protective circuits or =
>components(ie.-component/circuit installation into 
motor control wiring =
>and type and specific sizes of and sizes of any 
components).=20
>
>
>    Thank you,
>
>
>    Grant P. Mahalek
>    gmahalek-at-shaw.ca
>    403-948-6443(res)
>    403-880-2070(bus, cell)
>
>
>
>
>
>