Curtis 1212S Manual,
Rev. B
41
Step 4. Setting the Discharge Factor
4.a Resume driving the vehicle, with a heavy load.
4.b Pay attention to the battery voltage, BDI, and time.
4.c At some point, you will feel the vehicle become sluggish and notice the
battery voltage drop significantly with basic maneuvers. This is the fully
discharged point of the battery. Stop driving.
4.d The BDI should have indicated 0% before this point, to prevent the
battery pack from wearing out prematurely.
4.e If the BDI does not read 0%, reduce the Discharge Factor parameter
proportionately to the indicated remaining BDI. Use this formula to
determine the new setting:
New Discharge Factor = Present Discharge Factor * (1 – BDI%),
with the BDI% being expressed decimally (e.g., 90% = 0.90)
.
Step 5. Setting the Charge Factor and Start Charge Voltage
How you set the Charge Factor and Start Charge Voltage parameters depends
on how you want the BDI gauge to respond to partial charging. The traditional
method is to require a full recharge and not to reset the BDI gauge until the
battery is full. The 1212S can also be programmed to allow the user to stop the
charge in mid-cycle and display a proportional amount of charge, or “partial
charge” reading.
If you want to require a full charge to reset the BDI gauge:
5.a Set the Charge Factor to 10.0.
5.b Set the Start Charge Voltage equal to the Full Charge Voltage.
With these settings, the BDI will not recalculate until the very end of the charge
cycle, and the Reset Voltage—not the charge time—will trigger the BDI to 100%.
If you want to use the partial charge feature:
5.c Based on the Amp Hour rating of the batteries and the charger’s aver-
age amp output, initially calculate and set the Charge Factor using this
formula:
Charge Factor = 1.5 * (Battery amp-hrs / Charger amps).
5.d Starting with the dead battery from Step 4, plug in the charger. After
10 minutes of charging, measure the battery voltage with a meter. Set
the Start Charge Voltage parameter to this value.
APPENDIX C: BDI SETUP
