Wall Connector Application Note: DynamicPower Management

Overview................................................................... 2
Required Equipment.............................................3
Install the Energy Meter...................................... 4
Commission the System......................................9Troubleshooting.................................................... 13
Energy Meter Chime Indication.......................................13
Energy Meter LED Indication........................................... 14
Negative Site CT Value.......................................................14

Revision History.................................................... 15

OVERVIEWAs described in the Wall Connector Installation Manual, the Gen 3 Wall Connector should be installed with a40A circuit breaker for maximum power output. In the event that there is not enough capacity for a 40A
breaker in the electrical panel, a smaller breaker can be installed with a lower amperage configuration asfollows:
Circuit Breaker (Amps) Maximum Output(Amps)

230V Single-phase power
output (kW)400 V Three-phase power
output (kW)

40

32

7.4

22.1

32

25

5.8

17.3

25

20

4.6

13.8

20

16

3.7

1116

133

916

10

2.3

6.9

108

1.8

5.5

106

1.4

4.1

The alternative to a smaller breaker is a costly panel upgrade.
Dynamic Power Management is a new feature that enables Wall Connector to dynamically adjust EV
charging power based on live readings of the overall load in the panel. An energy meter is installed tomonitor live current in the panel; when panel loads are reduced, Wall Connector is able to increase charging
current up to a limit set by the installer.
NOTE: This feature is not supported on three-phase delta (typically 230V L-L) or open wye gridconnections. The most common grid connections are supported:• 1-phase 230V L-N• 3-phase 400V L-L (wye with neutral)
NOTE: If Neurio loses connection with Wall Connector, the maximum output defaults to 6A so as notto overload the system.

Supported System Configurations
Dynamic Power Management is compatible with single or three-phase systems where a single WallConnector is installed. Other system configurations are not supported at this time.

Wall Connector Application Note: Dynamic Power Management

2REQUIRED EQUIPMENT
The following equipment is required:• Energy meter kit:
◦ Tesla P/N 1938241-01-A (includes (1) CT)◦ Tesla P/N 1938241-02-A (includes (3) CTs)

1

Energy meter

2

Current Transformers (CTs)3

Voltage line harness

4

RS-485 communication harness
NOTE: The energy meter must be procured from Tesla as it ships with firmware required for thisapplication• Wago 3-, 4-, and 5-position lever nuts for splicing communication harness and energy meter voltage
harness
NOTE: The Wi-Fi antenna included in the energy meter kit is not used.

Wall Connector Application Note: Dynamic Power Management

3

INSTALL THE ENERGY METERCAUTION: Never perform work on live circuits. De-energize the electrical panel before continuing.
1. Attach the energy meter's mounting plate to the inside of the electrical panel, and push the meter
onto the plate.
NOTE: The energy meter requires 203 x 203 x 102 mm of space inside the electrical panel. Thisclearance allows for the space required for routing wiring to the energy meter.
NOTE: The maximum distance the energy meter can be installed from the Wall Connector(wired RS-485 connection) is 120 m.
2. Wire the meter voltage taps:
a. Connect the voltage line harness leads to a dedicated circuit breaker (not exceeding 20A) ofcorresponding phase inside the distribution board:
Voltage Harness Port/Wire Color

Distribution Board Connection

A/Brown

L1 breaker terminal

B/Black

L2 breaker terminal

C/GrayL3 breaker terminal

N/BlueNeutral bus barb. Plug the voltage line harness into the meter.
NOTE: If a dedicated breaker is not available, the voltage line harness can be spliced toexisting breakers if allowed in your jurisdiction.

Wall Connector Application Note: Dynamic Power Management

4

INSTALL THE ENERGY METER
Figure 1. Voltage Line Harness Wired to Dedicated Breaker (Top) or Spliced to Existing Breaker(Bottom) (Single Phase)

Wall Connector Application Note: Dynamic Power Management

5

INSTALL THE ENERGY METER
Figure 2. Voltage Line Harness Wired to Dedicated Breaker (Top) or Spliced to Existing Breaker(Bottom) (Three Phase)

3. Install the current transformers (CTs):a. Clip the CTs around Line 1, Line 2, and Line 3 - the main conductors feeding the panel.

Wall Connector Application Note: Dynamic Power Management

6

INSTALL THE ENERGY METER
NOTE: Ensure the "Source this Side" label faces away from the breakers, and towards thegrid.
Figure 3. CT Orientation in Relation to Power Flow (Label to Face Power Source, in this CaseGrid)b. Plug the CTs into the meter:
i. The CT measuring Line 1 can be plugged into either Port 1 or Port 4.
ii. The CT measuring Line 2 must be plugged into Port 2.
iii. The CT measuring Line 3 must be plugged into Port 3.
NOTE: It is critical that each CT have the correct voltage reference. Ensure the CT isplugged into the correct port based on the phase it is measuring.
Figure 4. CT Measuring Single Phase System (CT on L1, Plugged into Port 1)

4. Establish a hardwired RS-485 connection between the Energy Meter and Wall Connector using theincluded 2-conductor wire harness:a. Plug the provided wire harness into the port.
b. Extend the harness leads by splicing 1.5 mm2 shielded twisted pair cable to the harness.
c. If applicable, land the drain wire on the ground bar in the panel.

Wall Connector Application Note: Dynamic Power Management

7

INSTALL THE ENERGY METER
d. Locate the terminals on the backside of Wall Connector.
e. Land the wire corresponding to the red lead of the harness to the red port, and the black lead tothe white port.

f. Manage the communication wires so that they are not pinched when mounting the WallConnector to the wire box.

5. Energize the panel and turn on the circuit breaker(s). The energy meter will chime when it has
powered on.

Wall Connector Application Note: Dynamic Power Management

8

COMMISSION THE SYSTEM
1. Turn off any solar inverter(s) prior to commissioning. Turning off solar production ensures CT function
can be confirmed as all CT measurements should be positive when there is no solar.
2. Confirm the breaker feeding the Neurio meter has been turned on.
3. Follow the standard procedure to commission Wall Connector in Tesla One (see Wall Connector Device
Setup in Tesla Pros for complete instructions).
4. Ensure Wall Connector has been updated to firmware version 23.8.1 or greater. If Wall Connector is notconnected to Wi-Fi, follow the offline firmware updates procedure.
5. Once connected, the Neurio meter will automatically be detected. Select Meter to configure CTs andset the Max Conductor Limit.

Wall Connector Application Note: Dynamic Power Management

9COMMISSION THE SYSTEM
6. Select the Neurio meter to configure the CTs.

Wall Connector Application Note: Dynamic Power Management

10

COMMISSION THE SYSTEM
7. For each of the connected CTs, select the CT and set the Location to Conductor.

8. On the Meter screen, set the Max Conductor Limit. This value should be 80% of the electrical panel’s
rated limit.
◦ See Overview on page 2 for circuit breaker size options and the associated max conductor
current ampacity for each circuit breaker size.
◦ For example, the max conductor current ampacity for a 63A breaker would be 50A.

Wall Connector Application Note: Dynamic Power Management

11

COMMISSION THE SYSTEM

9. Test the system by turning on large loads in the panel and ensuring Wall Connector properly adjusts its
charge rate. Alternatively, temporarily set the max conductor current lower than the actual limit of theelectrical panel being measured. For example, if the conductor limit is 50A, temporarily set it to 32A.
Confirm that this current limit is maintained by the Wall Connector by turning on some loads thatwould exceed the limit.

Wall Connector Application Note: Dynamic Power Management

12

TROUBLESHOOTING
Energy Meter Chime Indication
Table 1.
ToneIndication

Description

Voltage check

One beep for each voltage wire that is connected.

Short Chime

Energy meter Wi-Fi
network started

Energy meter has started hosting its own Wi-Fi network. You
can join this network to configure the energy meter andconnect it to your own Wi-Fi network.

Long beep

Voltage warning(conditional)

Indicates that two wires are connected to the same phase.

Long Chimes

Energy meter joined
network successfully

Energy meter successfully joined your Wi-Fi network.

Failing tone

Energy meter failed tojoin network

Energy meter was unable to join your Wi-Fi network. Energy
meter will now start hosting its own Wi-Fi network again toallow you to re-connect to the energy meter and re-enter theWi-Fi credentials.

Short Beeps

Wall Connector Application Note: Dynamic Power Management

13

TROUBLESHOOTING
Energy Meter LED Indication
Table 2. Energy Meter LED Indication
LEDStatus

Behavior

Blue, then Green Flashes blue, then turns solid green (whetheror not comms wire is connected)

Energy Meter is Powered On

Green and Red

Energy meter is communicating with
Wall Connector

Flashes green and red

Negative Site CT Value
The CT values in the Commissioning Wizard should be positive. If a CT value is negative:
1. Confirm all solar production has been turned off. Solar production greater than home consumption
may result in negative readings
2. Confirm the CT is oriented correctly, with the "Source this Side" label facing toward the grid. If the CT
is not oriented correctly, physically flip it or check the Flip box in the Commissioning Wizard.

Wall Connector Application Note: Dynamic Power Management

14

REVISION HISTORY
Revision Date

Description

1.0

2023-09-13 Initial publication

1.1

2023-11-21• Updated to reflect Dynamic Power Management as name of feature• Updated to reflect Tesla One commissioning experience

1.2

2024-01-22• Updated Overview on page 2 to include note and new section on supported
system configurations• Updated Energy Meter LED Indication on page 14, removing old states andadding states when powered on and communicating with WC

Wall Connector Application Note: Dynamic Power Management15