Original Rev. 27-MAR-2006 Current Rev. 31-DEC-2007 Questions: ---------- - One box or Two ? - Location of box(es) ? - Location of the battery ? - Location of switch(es) ? - Connector or direct wiring to box(es) ? - Location of the coil ? - Function of switch(es) ? plan A just one push button to start the generator plan B just one switch OFF --> isolate the battery and ignition off ON --> connect the battery to the bus and ignition on momentary push --> start the generator - 6V or 12V system ? positive or negative ground ? Information: ------------ - Intent 6V Neg Gnd - Battery space is about 2 1/2" deep, 4" wide, 6" tall - The B25 battery is 12V 4.6 AH at 10 hour rating (0.1 C) to 10.5 Volts This is an NP5-12 battery. Looking down on the top of it, it is: 3.54" long, 2.75" wide, 4.17" height. Looking at it in the battery compartment from the side I would call this: 2.75" deep, 3.54" wide, 4.17" tall. - A rational 6 Volt 10 AH battery may be the NP10-6FR. The FR in the part number stands for Flame Retardant. This battery (in its "standard" orientation) is: 5.95" long, 3.84" tall, 1.97" deep. This may fit better an the lower chain guarde location. - Another rational battery is the NPX-50 6V A 10 hour capacity of 12 AH to an output of 5.25V A 1 hour capacity of 9 AH to an output of 4.8 V. Looking down on the terminals it is: 5.95" long by 1.97" wide and in this orientation they call it 3.84" height. Setting this battery upright in the standard orientation battery compartment looking from the side I would call it: 1.97" deep, 5.95" wide, 3.84" tall. Same as the battery above with the same problem, i.e. too wide. - Summary of two different 6 Volt batteries: Case Connector Conn. Type Length Depth Height Height Set In Capacity ---------- ------ ----- ------ ---------- ------ -------------- NP10-6(FR) 5.95 1.97 3.70 3.84 0.39 10 AH (20 hrs) LC-R0612P 5.945 1.969 3.701 3.937 0.408 12 AH (20 hrs) - Box space is about 2" to 3" deep, 4" wide, 6" tall - Assume 6.3 V with no charge 7.2 V generator set point 5.6 V LDO regulator - Standard die-cast box sizes are: viewed from side as installed deep wide tall vol manuf ---- ---- ---- --- ----- 2.2 3.7 4.7 38 bud as on the B25 2.3 4.7 4.7 51 bud 2.0 3.2 6.0 38 bud 2.9 4.9 4.9 70 ham 1590 2.2 4.7 4.7 49 ham 1590 3.1 3.9 5.9 71 ham rolec Box: BX39B Expected Orientation longest dimension horizontal Length: external 6.57 to 6.75 internal 6.41 to 6.63 Height: external 4.58 to 4.77 internal 4.42 to 4.61 Depth: external 4.175 internal 3.93 to 4.00 Wall Thickness: about 80 mils Height between Ribs: 3.865 Ribs Come In From Sides: Top and Bottom Slant Angle: about 1.36 degrees - Current that is required to charge 1 nFd to 5 Volts in 1 usec. V x C Q = V x C I x T = V x C I = ------- T 5 Volts x 10**-9 F -------------------- = 5 ma 10**-6 sec - What R makes a 1 usec RC with 1 nFd 1 K Ohm - The "official" room temperature resistance of the generator field coil is: 2.648 Ohms. This is from a 4 wire measurement. - The "official" inductance of the field coil with zero DC current in it is: 7.078 mH. The Q is about 1.38 - The "official" L/R time constant of the field coil is 2.67 msec. - List of the blocks: Regulator V_Battery input to 5.6 Volt output 50 ma with over voltage and over current protection Generator Output Regulator This block regulates the current in the Field Coil to control the generator's output Voltage. This must allow the generator to "build up". CD_Ign SCR firing circuit Receive and condition the timing signal and make the SCR firing Gate signal. Capacitor Charging circuit From a 6V to 7.5V supply charge a 1.5 uFd capacitor to 350V - 375V in 10 msec. - Measure two standard ignition coils: Auto-Lite Primary 1.65 Ohm 7.42 mH Q 8.0 Bosch Primary 1.86 Ohm 9.29 mH Q 6.1 - What is the rate of current rise in these coils: dA V assume 350 Volts is applied across the primary -- = --- 7.42 mH rises at 47 Amps/msec dt L 9.29 mH rises at 38 Amps/msec Generator Regulator Design Issues: ---------------------------------- - Goal is to minimize the power that is required to excite the field of the generator for a given generator output. - The core of the field coil is not laminated so it will suffer from significant edy current losses. - Ideally one would use the inductance of the field coil and a pwm switch to control the current in the field coil (with a free-wheel diode or second FET switch to conduct when the switch to the external supply is open. - The standard linear regulator will waste a lot of power in the middle output range of the cenerator whent he field coil is about half excited. The standard linear regulator is OK at full excitation (assuming one does not waste a ton of base current in a bipolar pass element). - Will a switching aproach have a lower loss once the edy current losses are considered ? Reducing the switching frequency may help reduce the edy current losses. - The switching approach must take into consideration the L/R time constant of the Field Coil. "Lucas" Amp Gauge ----------------- Checked the internal resistance of the after market Lucas Amp gauge. With 7.5 Amps flowing through it, it has a drop of 130 mV. This implies an internal resistance of 17.3 milli-Ohm. One foot of #22 wire is 16.5 milli-Ohm. The scale of this gauge must be about 10 Amps full scale. CD Ignition Design Issues: -------------------------- - What numbers to use for the "official" DC resistance and the inductance of the primary of the ignition coil. - Because the discharge capacitor charges through the primary of the ignition coil, the inductance of the primary of the coil sets a limit on how quickly the capacitor can be recharged. Total IC and IC Sharing: ------------------------ - HC14 Schmitt for: CDI points signal filtering and FET Driving, and for Generator Field Coil Regulator FET Driving - HC74 FF for: CDI DC/DC Converter and "Armed" circuit, and for Generator Field Coil Regulator - HC123 ReTriggerable for: CDI points signal filtering - HC221 Oscillator for: CDI DC/DC converter and Spark Tester, and for Generator Field Coil Regulator Measure 4 Toroid Cores ---------------------- All tests use a 10 turn coil to measure the inductance and a separate 10 turn coil to add DC Amp-Turns from a current source. Single Feroxcube OD = 0.870 ID = 0.540 Thick = 0.25 area of center opening = 0.229 sq inch Percent of the Current Zero Current uH Q ma Amp-Turns Inductance ---- ---- ------- --------- ------------ 332 12.2 open 298 5.88 24.5 90 % 260 6.42 50.0 78 % 214 6.83 75.2 64 % 170 6.93 100.5 51 % 142 6.81 125.6 43 % Double Feroxcube OD = 0.870 ID = 0.540 Thick = 0.50 1.37" per turn area of center opening = 0.229 sq inch Percent of the Current Zero Current uH Q ma Amp-Turns Inductance ---- ---- ------- --------- ------------ 672 17.7 open 584 4.19 25.2 87 % 511 4.87 50.2 76 % 418 5.69 75.3 62 % 337 6.51 100.4 50 % 271 7.17 125.0 40 % Vicor Gray OD = 1.5 ID = 0.735 Thick = 0.255 1.32" per turn area of center opening = 0.423 sq inch Percent of the Current Zero Current uH Q ma Amp-Turns Inductance ---- ---- ------- --------- ------------ 483 24.2 open 460 5.90 25.0 95 % 439 6.11 50.2 91 % 411 6.38 75.4 85 % 383 6.67 100.8 79 % 354 6.96 125.3 73 % 327 7.23 150.0 68 % 300 7.48 174.8 62 % 268 7.75 200.7 55 % 236 7.98 225.8 49 % Now test the low mu black core from the power entry module PFC circuit. Is this a Ferrite or is it Powered Iron because it may only need to turn on/off at 60 Hz ? A 10 turn coil gives 10.1 uH A 30 turn coil gives 70.4 uH There is the beginning of a hint of saturation with 30 Amp-Turns of DC current. Set the scale of the required inductances: Primary of a Forward converter, for an ON time of 5 usec with an applied voltage of 7V, want only 100 ma flowing in the primary 0.1 Amp V --------- = 2 x 10**4 Amps/sec L = ------- 5 usec dA/dt 7V -------------------- = 350 uH 2 x 10**4 Amps/sec Primary of a Flyback converter, for an ON time of 5 usec with an applied voltage of 6V, want 2.0 Amps flowing in the primary 2.0 Amp V --------- = 4 x 10**5 Amps/sec L = ------- 5 usec dA/dt 6V -------------------- = 15 uH 4 x 10**5 Amps/sec Items to Purchase ----------------- - Battery - Box - Power N Channel Enhancement FET - HC Logic 31-DEC-2007 ----------- Scope pictures of the pickup of the edge of a thin disk magnet with an Allegro A1323LUA-T sensor. The poles of the magnet are on its big flat surfaces and it is the edge of the magnet that faces the sensor. The diameter of rotation of the magnet is 1.100". The thin face of the sensor faces the edge of the magnet. The leads of the sensor run outwards radially from the center of rotation of the magnet. Get pictures at 3 different crankshaft speeds: 600, 3000, and 6000 rpm crankshaft. That is: Magneto Sensor dt for This dt in Crankshaft Magneto or Spark Output 1 Volt dV Crankshaft RPM RPM Period Volts PP at 0V Cross Degrees ---------- ------- -------- --------- ----------- ---------- 600 300 200 msec +2.2 -2.4 500 usec 1.80 deg 3000 1500 40 +2.2 -2.3 80 1.44 6000 3000 20 +2.0 -2.2 50 1.80 5-JAN-2008 ---------- The Allegro A1323LUA-T sensor is rated for: the absolute maximum supply voltage is 8.0 Volts the nominal supply Voltage is 5.0 Volts and it nominally draws 5.6 ma it wants its output current to be <= 1.0 ma with <= 1.0 ma of output current it has an output resistance of 3 Ohms maximum it specifies a minimum output load resistance of 4.7 k Ohms and a maximum output load capacitance of 10 nFd with the narrow surface up (the surface with the recess down) and the leads toward you then: left lead (1) is power, middle lead (2) is ground, right lead (3) is output. the narrow surface is the surface nearest the hall sensor. The LM339 quad comparator has the following characteristics: the absolute maximum supply voltage is 36 Volts running from +5 Volts the Fairchild LM399AN over the 0 C to +70 C range has the following characteristics: Input offset Voltage 4.0 mV max Input bias current 400 na max so input resistance > 10k Ohm could double the input offset Input common mode range 0 to +3.0 Volts The input pins are the bases of PNP transistors with grounded collectors. Supply current (all 4 comparators) < 2 ma Large Signal Response time (with a large overdrive) 300 nsec typ Output Voltage < 700 mV with and output current <= 4 ma Output leakage current < 1.0 uamp