walkman
Well Known Member
So I'm at the point of powering up my new electrical system and checking out systems and calibrating the EIS 4000. I'm seeing some measurements that I just don't believe. This is a z-12 architecture, 1 battery with 2 alternators. im using a b&c sd-8 as the stsndby alt.
This is all with engine off.
With a battery at 12.46v as measured with my digital multimeter I'm seeing about 11.4 volts at the main buss as measured on the EIS and confirmed with my multi-meter at several ground and buss locations.
If I switch off the master and turn on the e-buss feed (comes off the batt via a diode) I'm seeing very close to battery voltage.
This indicates there is a 1v drop through the contactor path.
I have two Hall effect sensors for ammeters. The first is on the battery positive cable between the battery and the contactor. The second is on the b lead for the standby alternator (after the regulator, between it and the buss).
With all breakers pulled and nothing on but the EIS, map sensor, and the EIS warning lamp (replaced with led) I'm seeing -5 for the amp1 and some tiny negative number (well less than 1 amp) on amp 2.
If I switch off the master and use the e-buss feed I'm seeing -4. That part sounds right, that the contactor take about 1amp to energize. I am just having a real hard time believing the EIS and map sensor are pulling 4 amps. Does that sound right?
When I turn on the strobe, landing, taxi, nav lights I see increases in discharge rate that seem sane.
So, I've got a 1v drop and a 4amp current drain that seems odd to me. Is it normal?
The only thing I haven't done yet is pull the fuse on the standby alternator b lead. Is it possible this is actually draining the battery and causing both issues?
This is all with engine off.
With a battery at 12.46v as measured with my digital multimeter I'm seeing about 11.4 volts at the main buss as measured on the EIS and confirmed with my multi-meter at several ground and buss locations.
If I switch off the master and turn on the e-buss feed (comes off the batt via a diode) I'm seeing very close to battery voltage.
This indicates there is a 1v drop through the contactor path.
I have two Hall effect sensors for ammeters. The first is on the battery positive cable between the battery and the contactor. The second is on the b lead for the standby alternator (after the regulator, between it and the buss).
With all breakers pulled and nothing on but the EIS, map sensor, and the EIS warning lamp (replaced with led) I'm seeing -5 for the amp1 and some tiny negative number (well less than 1 amp) on amp 2.
If I switch off the master and use the e-buss feed I'm seeing -4. That part sounds right, that the contactor take about 1amp to energize. I am just having a real hard time believing the EIS and map sensor are pulling 4 amps. Does that sound right?
When I turn on the strobe, landing, taxi, nav lights I see increases in discharge rate that seem sane.
So, I've got a 1v drop and a 4amp current drain that seems odd to me. Is it normal?
The only thing I haven't done yet is pull the fuse on the standby alternator b lead. Is it possible this is actually draining the battery and causing both issues?