<![CDATA[DLMS Disconnect Control (Class 70) Remote Cut-off and Reconnection State Machine]]>Engineering Guide: Disconnect Control (Class 70)

Managing internal contactors for demand limiting or prepayment requires strict adherence to the Class 70 state machine defined in IEC 62056-62.

Object Identification

  • OBIS Code: 0.0.96.3.10.255 (Disconnect Control 1)
  • Class ID: 70

Control Methods

  • Method 1 (remote_disconnect): Opens the contactor (Disconnects supply).
  • Method 2 (remote_reconnect): Closes the contactor or enters 'Ready for Reconnection' state.

Output State Validation (Attribute 2)

Control State Value Meaning Physical Contactor Status
0 Disconnected Open (No power)
1 Connected Closed (Power active)
2 Ready_For_Reconnection Open (Awaiting manual button press on meter)

[!IMPORTANT]
Safety regulations in many jurisdictions forbid immediate remote closure if someone is working on site. Setting control_mode = 2 transitions the meter to state 2, requiring the consumer to press the meter physical push-button to complete the circuit.

]]>https://dlms.sharur.org/topic/30/dlms-disconnect-control-class-70-remote-cut-off-and-reconnection-state-machineRSS for NodeFri, 16 Oct 2026 19:49:17 GMTSat, 22 Aug 2026 12:36:03 GMT60<![CDATA[Reply to DLMS Disconnect Control (Class 70) Remote Cut-off and Reconnection State Machine on Sat, 22 Aug 2026 12:36:05 GMT]]>In the meter firmware, contactor pulse duration is controlled via Attribute 4 (output_signal). We configure a 200ms pulse for the magnetic latching relay to prevent coil overheating.

]]>https://dlms.sharur.org/post/69https://dlms.sharur.org/post/69Sat, 22 Aug 2026 12:36:05 GMT<![CDATA[Reply to DLMS Disconnect Control (Class 70) Remote Cut-off and Reconnection State Machine on Sat, 22 Aug 2026 12:36:04 GMT]]>From field experience: Always read Attribute 3 (control_state) immediately after executing remote_reconnect. If the meter is configured in Safety Mode, the state will read 2 (Ready_For_Reconnection) rather than 1 (Connected). The consumer display will show a blinking reconnect icon.

]]>https://dlms.sharur.org/post/68https://dlms.sharur.org/post/68Sat, 22 Aug 2026 12:36:04 GMT