diff --git a/libraries/AP_HAL_ChibiOS/hwdef/CUAV-7-Nano/hwdef.dat b/libraries/AP_HAL_ChibiOS/hwdef/CUAV-7-Nano/hwdef.dat
index eea49e50f0..f6eabe6f2f 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/CUAV-7-Nano/hwdef.dat
+++ b/libraries/AP_HAL_ChibiOS/hwdef/CUAV-7-Nano/hwdef.dat
@@ -102,6 +102,7 @@ PF3 ADC3_6V6 ADC3 SCALE(2) ANALOG(12)
 # pin6 on AD&IO, analog 13
 PC3 ADC1_3V3 ADC1 SCALE(1) ANALOG(13)
 
+define HAL_BATT_MONITOR_DEFAULT 4
 define HAL_BATT_VOLT_PIN 9
 define HAL_BATT_CURR_PIN 8
 define HAL_BATT_VOLT_SCALE 10.1