diff --git a/libraries/AP_BattMonitor/AP_BattMonitor_config.h b/libraries/AP_BattMonitor/AP_BattMonitor_config.h
index e15909c143..14a1fa7d28 100644
--- a/libraries/AP_BattMonitor/AP_BattMonitor_config.h
+++ b/libraries/AP_BattMonitor/AP_BattMonitor_config.h
@@ -83,7 +83,7 @@
 #endif
 
 #ifndef AP_BATTERY_SUM_ENABLED
-#define AP_BATTERY_SUM_ENABLED AP_BATTERY_BACKEND_DEFAULT_ENABLED
+#define AP_BATTERY_SUM_ENABLED AP_BATTERY_BACKEND_DEFAULT_ENABLED && (BOARD_FLASH_SIZE > 1024)
 #endif
 
 #ifndef AP_BATTERY_TORQEEDO_ENABLED