diff --git a/logs_service/services.py b/logs_service/services.py
index 2973bab..5c5be51 100644
--- a/logs_service/services.py
+++ b/logs_service/services.py
@@ -111,7 +111,7 @@ class MbTankService(MbService):
         # D2: radar_low_reg
         values = self.mb.read_holding_registers(0, 6)
         if values is None:
-            return
+            raise AssertionError('failed to load current state')
         self._curr_state = {
             "level": values[0],
             "status": values[5],
@@ -141,7 +141,7 @@ class MbPumpService(MbService):
         off = 16
         values = self.mb.read_holding_registers(16, 36 - off)
         if values is None:
-            return
+            raise AssertionError('failed to load current state')
         with self._lock:
             # определение запущенного насоса
             pr = -1