diff --git a/sma/README.md b/sma/README.md
index eff2e336..bbb61b63 100644
--- a/sma/README.md
+++ b/sma/README.md
@@ -8,11 +8,12 @@ nymea plug-in for SMA solar equipment.
 * SMA speedwire Meters
 * SMA speedwire Inverters
 
-> Note: the SMA battery equipment is still missing due to testing possibilities. Will be added as soon someone can with the apropriate setup.
+> Note: the SMA battery equipment is still missing due to testing possibilities. Will be added as soon someone can with the appropriate setup.
 
 ## Requirements
 
 * The package "nymea-plugin-sma" must be installed.
+* The speedwire port `9522` must not be clocked for UDP packages in the network.
 
 ## More
 https://www.sma.de/en/