Mqtt status with array in json

Hi! I have the following MQTT topic here:
tele/sonoff4/SENSOR {“Time”:“2018-10-17T19:22:02”,“ENERGY”:{“Total”:0.178,“Yesterday”:0.000,“Today”:0.178,“Power”:2631,“Factor”:1.00,“Voltage”:231,“Current”:10.865}}

how do I access this from homeassistant?
I’m trying:
sensor:

  • platform: mqtt
    state_topic: “tele/sonoff4/SENSOR”
    value_template: ‘{{ value_json.Energy[Voltage] }}’
    unit_of_measurement: V
    name: boiler_v

But that doesn’t work. What is wrong?

Ha, must be “Voltage”, now it works.