Outback Power Systems FLEXmax Extreme Owners Manual - Manual (Page 20)

Installation
18 900-0150-01-00 Rev A
Battery Sense Terminals
The remote Battery Sense terminals are used for accurate voltage monitoring. These terminals connect directly
to the batteries. Using the controller’s main battery cables for voltage sensing is less accurate. This is due to
voltage rise caused by charging currents on the battery conductors.
Terminals and are the – and + terminals for the Battery Sense function. These terminals are colored
black (-) and red (+) for easy reference. A twisted-pair cable is recommended. (See wire sizing on page 16.)
IMPORTANT:
The MATE3 display shows the system voltage as measured at the battery terminals of
various devices. (See Figure 26 on page 29.) This voltage is used for generator starting
and other functions.
 If no other devices are present, it will show the reading of the FLEXmax Extreme.
 If OutBack inverters are present, the inverter voltage replaces the FLEXmax
Extreme as the system voltage reading.
 If the FLEXmax Extreme Battery Sense terminals are in use, this reading replaces
the inverter or the regular charge controller readings as the system voltage.
 The FLEXnet DC Battery Monitor is the highest priority and will replace the
Battery Sense reading as the system voltage.
The Battery Sense reading is still shown on the Charge Controller screen. (See Figure 27
on page 30.) This reading is still used to adjust the FLEXmax Extreme charging.
This function operates automatically when it detects a voltage within 2 volts of the battery voltage reading at
the charge controller’s main terminals. If the reading varies by more than 2 volts, the Battery Sense function is
disabled. The assumption is that the terminals are not connected. (If the terminals are connected, there may be
a wiring problem.)
The MATE3 allows the user to calibrate the battery meter at the charge controller’s main terminals. (See page 45
and the MATE3 manual for more information.) This calibration does not affect the Battery Sense function. If
Battery Sense is in use, calibration changes can be made, but will have no effect until Battery Sense is disabled.
Figure 15 Battery Voltage Sensing
External Fault Terminals
The External Fault terminals are used to make connections to the OutBack Ground Fault Detector/Interruptor
(GFDI) product. A single wire is run from one of the yellow terminals ( or ). A second single wire is run
from one of the purple terminals ( or ). Terminals and are the most commonly used. These wires
are connected to a normally-open set of contacts on the OutBack GFDI. Figure 16 and Figure 17 show terminals
to without the rest of the control terminal block.
NOTE: Overcurrent protection is
not shown. Recommended
protection for sense conductors is:
 Fast-acting device
 80 Vdc or greater
 1 A or smaller
 Cold resistance 10 ohms or less