Paul Wallace wrote:
My Link-10 is going through a reset at random times when the inverter
is switched to drive. I've looked down to see the display switched
to blinking volts more than once.
This is usually caused by the Link-10 momentarily losing its 12v power.
If the power dips below about 10.5v, the display blanks. When the power
goes back up above this, the display will be blinking and it will have
lost certain values (like amphours).
The Emeter is powered by an isolated DC/DC converter.
Where does this DC/DC converter get its power? From the car's 12v
system, or from your DC pack voltage? The pack voltage probably dips
under load. This dip either directly makes the Link-10's DC/DC drop out,
or it causes the car's main 12v DC/DC converter to momentarily sag, so
the 12v falls, and this makes the Link-10's DC/DC sag.
I wasn't anticipating too much noise would make it through at a
magnitude great enough to cause this sort of problem. The current
shunt wires are twisted together from the shunt until they reach the
Deutch connector, along with the voltage sense wires.
The shunt, and the prescaler wiring won't cause this sort of reset
problem. They can make the display blank; but they won't cause the meter
to reset and forget the amphour reading etc.
Since the front panel says Link-10, I'm thinking that it should have
the EV filter already installed. Has anyone added extra filtering to
mitigate noise getting into the E-meter?
It may, or may not have the EV filter inside. Physically, the filter is
a 1000uF 35vdc electrolytic capacitor across the Link-10's power input,
plus a 1N4001 diode and 3.3 ohm resistor in series. Bad ASCII schematic
(view with fixed width font like Courier).
+12v power____|\|____/\/\________+12v power to Link-10
from DC/DC |/| 3.3ohm |
1N4001 resistor _|_+
diode ___ 1000uF 35vdc capacitor
common________________________|__common (NOT ground!)
Without the filter, it only takes a few millisecond power dip to reset
the meter. With the filter, it takes more like a half-second power dip.
You can add this filter externally yourself. It won't hurt to add it
again, even if it's already inside. A schottky diode (1N5818 etc.) is a
slightly better choice than the 1N4001. There is no upper limit for the
capacitance; bigger is in general better.
--
Any intelligent fool can make things bigger, more complex, and more
violent. It takes a touch of genius, and a lot of courage, to move
in the opposite direction. -- Albert Einstein
--
Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
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