Jump to content

Franky

Members
  • Content Count

    4
  • Joined

  • Last visited

Community Reputation

4 Neutral

About Franky

  • Birthday 01/01/1980

More Information

  • Aircraft
    LSA
  • Location
    Melbourne
  • Country
    Australia
  1. Franky

    SSB Lithium Iron batteries

    It looks like the SSB batteries are all Lithium Ion Phosphate not Lithium Iron Phosphate batteries They are very different beasts. Franky
  2. Franky

    SSB Lithium Iron batteries

    Hi Bruce The ETX680 does have cell balancing circuitry and other stuff, see excerpt from manual below. I think the problem is that there spec for minimum charge voltage is a little low. ETZ - BMS All EarthX integrated BMSs continuously monitor each cell’s voltage as part of the cell balancing and over-charge protection. If the voltage of a cell exceeds the others, the BMS circuits will work to reduce that cell’s charge level. This ensures that the charge level of all the cells remains equal, even with the high discharge (> 100Amps) and charge current (>10Amps) of your vehicle. A cell can be permanently damaged if over-charged (over-voltage) just one time. The BMS has circuitry to disconnect the battery from the charging system (plug-in charger or your vehicle) if the voltage exceeds 15.5 volts (an over-charge condition). The ETX Hundred Series batteries have enhanced over-charge protection; see the ETX - Hundred Series section below for more details. The ETZ BMS has short circuit protection, but it is not resettable or repairable. ETX - BMS The ETX series BMS has all the features of the ETZ series, plus over-discharged protection (completely draining the battery), excessive cranking protection, and short-circuit protection. The BMS disconnects the battery from the load if it is drained to less than 5% remaining charge (an over-discharge condition). An over-discharged battery typically has a voltage less than 11.5V. If the BMS disconnects the battery, the voltage reading of the battery will be zero volts. Excessive cranking protection logic includes temperature monitoring to limit “high current use” (engine cranking) to 10 -30 seconds in any 60 second period. If the battery terminals are “shorted” (or a low impedance load is connected across terminals), which causes the battery volts to instantaneously drop to a very low level, the battery will disconnect from the load to protect the cells and BMS from damage (short circuit protection). If the BMS disconnects due to excessive cranking protection or short circuit protection, the BMS will automatically reconnect after a cooldown period (typically 1-3 minutes). The ETX series is designed for short circuit protection > 1000 Amps. Franky
  3. Franky

    SSB Lithium Iron batteries

    A few observations on EarthX batteries, specifically the ETX680 This was installed in an aircraft with a 912ULS and standard regulator mounted on the cockpit side of the firewall. The fault line was connected to the EFIS so any fault condition was immediately apparent. Not long after install a fault condition was reported which after consultation with the manufacturer it was decided that the fault was indicating that the cells were not quite balanced. The suggested solution was to charge the battery at a slightly higher voltage (14.2v) instead on the 13.8v which was output from the rotax regulator. The battery was removed and charged at the higher voltage and the fault disappeared. I decided that because the charging voltage was on the bottom end of the spec (13.9v to 14.6v), that the charging voltage on the rotax regulator would be increased to 14.2 volts. At this increased voltage there have still been 3 occaisons over 50hours of flying where a fault has been indicated, but the fault condition soon clears after 5 or 10min or so. Possibly a slightly higher charge voltage would stop this but I havent bothered. My suspicion is because of the cell balancing circuitry, a higher charge voltage is beneficial in helping the cell balancing operate. ( no higher than 14.6v of course) Although the manual says “no jump starting from a car battery” the warranty section clarifiies no jump starting from a battery of significantly higher capacity. It does not rule out jump starting persay. This indicates to me that jump starting from a small lithium powercube would not be a problem. The battery cranks the rotax so well I think more care needs to be taken in choke/throttle settings so that as the engine fires up excessive load is not placed on the sprag clutch. As an aside, when the battery is partially flat, the battery charge current in the above environment is about 8amps. Under this condition with all the other loads the regulator temperature reaches about 70deg on a 25deg day. (regulator output approx 18amp under this condition) Very happy with this battery, saves a few kgs, fantastic cranking regardless of ambient temperature; except of course for the price, although it is supposedly lasts a lot longer. Franky
  4. I have had a stratux installed in my RAA LSA for about 6 months. I was prompted by seeing an increase in the number of GA planes who have adsb out over the past year or so. (using flightradar) I have had about 6 instances where see and avoid was inadequate and the adsb paint enabled appropiate action to be taken. It is a better solution than any method that relies on adsb receiving ground stations because you are receiving the signal directly from the aircraft with accompanying lower latency. You have to be careful interpreting altitude data because it is based on standard pressure and needs to be adjusted for local qnh (hint to bevan) Although most RAA aircraft (except mine) and many GA aircraft dont have adsb out, it is just another tool that does not replace see and avoid. It is especially useful at busy airports which have RPT aircraft and therefore will all have adsb out. Also good when near airports and flying VFR routes. I wish casa would make the fitment of adsb out to aircraft more economic by accepting gps sources with lower integrity. Franky
×