Technical Note: TN0033 - Rev 03


The SP PRO and Outback Flexmax 60/80 regulator can be connected and configured so that the charging stage of the SP PRO will change to Float when signalled by the Flexmax regulator.  This keeps both working to the same charge stage.

SP PRO Configuration

The SP PRO is configured by default to accept the Float input on Digital Control Input

1.  Float Stage Input would only need to be changed from default if Digital Control Input 1 is being used for another purpose. 
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This is set to accept the Float signal from the Flexmax regulator.

Flexmax 60/80 Regulator Configuration

The Flexmax 60/80 must be set to turn AUX Output on when in Float.

 In MAIN menu, select AUX.

In AUX MODE press NEXT until Float is displayed.

Press MODE and set to Auto


Note: The AUX MODE Float function is only active when the Flexmax is actually producing power.

SP PRO and Flexmax Wiring

The AUX Output provides 12VDC which is compatible with the SP PRO Digital Control Input.

1.  Connect AUX+ to DGTL CTRL IN 1 POS terminal on Expansion Card.

2.  DGTL CTRL IN 1 NEG connects through to AUX -

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Note: Digital Inputs are independent current limited inputs which are ‘opto’ isolated and reverse polarity protected.

Test Operation

In AUX MODE, press Mode to change from AUTO to ON.  The SP PRO will also switch to Float stage.  If this doesn’t occur, check the wiring and settings in both SP PRO and Flexmax.

Set Mode back to AUTO for normal operation.

 Note: The SP PRO will only switch back to initial when the battery voltage falls below the Initial Return voltage.

Additional Information
Visit the Selectronic: Knowledge Base or contact Selectronic via the Customer Portal.