----- Original Message -----
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 -----
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).
Thank you,
Grant P. Mahalek
403-948-6443(res)
403-880-2070(bus, cell)