zappi v2Built-in Protection

  1. Built-in Protection
  2. RCD Protection
  3. Loss of PEN Conductor
  4. Loss of PE
  5. Welded Contact
  6. Over-current
  7. Over and Under-voltage
  8. Thermal Limit

1. Built-in Protection

zappi has a number of protection features built into the device to make it safe and simple to install.

2. RCD Protection

The RCD (Residual Current Device) will trip the output from zappi if there is an electrical fault to ground. The RCD is similar to the protective devices found in most domestic consumer units (the “fuse box”) but the standards for electric vehicle charging require additional protection for small DC leakage currents. zappi provides this protection in accordance with EN 62955 (Integral 30mA Type A RCD + 6mA DC leakage protection).   Local wiring regulations should be checked to confirm whether an additional upstream RCD is also required.

If there is an electrical fault to ground and the RCD operates the zappi display will show RCD Tripped!

To reset the zappi, make sure that the fault has been removed and then press button for three seconds.

 

3. Loss of PEN Conductor

The Protective Neutral and Earth (PEN) conductor refers to part of the electricity cable to the property. If this conductor is damaged there is a danger that the chassis of the electric vehicle being charged will become “live” and cause an electric shock. BS7671:2018-amd1:2020 part 722.411.4.1(v) requires that extra protection is provided to prevent an electric shock – either by fitting an extra earth electrode or through a device which detects the fault and disconnects the supply.

zappi has the protection built in (patent pending) and will disconnect the output if it detects a problem with the PEN conductor or it detects that there may be any electric current flowing through the chassis of the EV. This built in protection means that there is no need to install an extra earth electrode with the zappi.

If zappi detects a problem with the PEN conductor then the display will show PEN Fault!

To reset the zappi, check the continuity of the earth cable and then press the  button for three seconds.

4. Loss of PE

zappi is able to measure the continuity of the protective earth conductor (the earth wire) on the supply cable. If the earth is disconnected or has a high impedance then zappi will trip and the display will show PE not connected!

To reset the zappi, make sure that the fault has been removed and then press the button for three seconds.

5. Welded Contact

zappi includes protection to make sure that the supply to EV is disconnected if there is a problem with the circuit breaker. This includes a situation where the contacts on the breaker are welded together. This is a specific requirement of the Renault “Z.E. Ready” and ASEFA “EV Ready” standards (e.g. requirement for Nissan).

If zappi detects a problem with a welded contact then the display will show RLY WELDED!

If this happens and the fault cannot be reset by pressing the button for three seconds then please contact myenergi technical support at support@myenergi.com.

 

6. Over-current

If here is a problem with the equipment on the EV which charges the vehicle’s battery, too much current may be drawn from the supply. If this happens, zappi is not able to control the charge rate as expected and it could lead to problems with overheating or tripping of the main circuit breaker to the zappi.

zappi provides additional protection in accordance with the EV Ready standard by opening it’s built-in contactor and isolating the EV if it detects that vehicle is drawing more than 125% of the maximum current communicated to it by the zappi.

If zappi detects an over-current then the display will show Over Current!

To reset the zappi, make sure that the fault has been removed and then press the button for three seconds.

7. Over and Under-voltage

zappi will also isolate the supply to the EV if it detects a problem with the electricity supply voltage. The nominal supply voltage is 230V but zappi will trip the output if the measured voltage is more than 12% above or below this level for five seconds.

The zappi display will show Over Voltage! or Under Voltage!

To reset the zappi, unplug the EV and then press the button for three seconds.

 

8. Thermal Limit

zappi also includes protection against overheating. If zappi gets too warm it will attempt to reduce the current being drawn by reducing the EV charge rate. If this happens you will see theicon on the main display.

If the problem continues and the zappi‘s internal temperature continues to rise then it will trip the output to the EV and the display will show Overheating!

zappi will resume normal operation once the temperature drops.