SharpV earth grounding - SharpV | SharpOS 12.7

AutoVu Handbook for SharpV Fixed Installations 12.7

series
SharpV | SharpOS 12.7
revised_modified
2019-08-21

To prevent hardware damage in regions that experience frequent thunderstorms, SharpV cameras must be properly earth grounded.

Before you install a SharpV camera outdoors, investigate the lightning frequency for the region.

SharpV grounding guidelines

Depending on the installation, there might be many ways that the camera can be properly grounded. If you respect the following general guidelines, you can be sure that the camera is safely grounded.

  • You must install an earth-grounded surge protector between the Ethernet switch and the camera. The surge protector that is protecting the camera should be as close as possible to the camera.
  • Ground all devices that are in the proximity of the camera to a single point. This ensures that the system is not damaged due to a difference in voltage between devices.
  • The ground bonding point should be as close as possible to both the camera and the surge protector.

Earth ground or safety ground

If power is supplied to the enclosure using a three-wire cable (positive, neutral, and ground), you should not use the cable's ground wire to ground the camera. This is a safety ground and cannot protect the hardware from a lightning surge. To ground the camera, you must use a proper earth ground at the base of the mounting pole (as close as possible to the camera), or create a floating circuit.

Grounded circuit or floating circuit

It is recommended that you install the camera with an earth ground. However, if you install the SharpV camera on a non-conductive surface, (for example, a wooden pole), you can leave the camera and mount as a floating circuit, and earth grounding is not required.

Example: Earth-grounded SharpV installation

Component Description
A SharpV camera ground:
  • Using appropriate wire lugs, connect a short 14 AWG wire between a mounting bolt (M6 x 1mm, max length 9mm, not included) on the bottom of the camera body and the grounding point in the enclosure.
    WARNING: The mounting bolts on the top of the camera body cannot be used as a grounding path.
  • If you connect the camera mount to the bottom of the camera, you must sandwich the grounding wire lug between the mount and the mounting bolt.
  • In this example, the camera's ground wire runs to the grounding point in the enclosure. It would also be acceptable to run the camera ground wire to the grounding strap that is installed on the pole.
B Grounding strap:
  • In this example, the camera and the ungrounded plastic enclosure are mounted on a conductive metallic pole. The pole acts as a grounding path between the grounding strap and the earth ground at the bottom of the pole.
C NEMA enclosure:

In this example, the NEMA enclosure includes the following components:

  • PoE+ injector: Power-over-Ethernet; 802.3at Type 2 (25.5 W). You can install the injector up to 100 M (330 ft.) from the camera.
  • Surge protector: You must install a surge protector between the camera and all other electrical hardware in the system. Install the surge protector as close as possible to the camera and bond the electrical hardware to a common grounding point, as close as possible to the devices.
    NOTE: If the enclosure is not mounted near the camera, you can install a secondary enclosure for the surge protector, or install an IP67-rated inline surge protector near the camera.
  • Grounding bus bar: Ground all devices to a single point. This ensures that the system is not damaged due to a difference in ground voltage potential (under surge conditions) between devices.
    IMPORTANT: You must minimize the distance between the electrical hardware and the grounding point.
D Ethernet switch:
  • If required by the switch manufacturer, install a surge protector close to the switch.
  • In this example, the switch is located in a nearby building. Alternatively, you could install the switch in the NEMA enclosure.
E Power cables:
  • In this example, power is supplied to the enclosure using a 3-conductor cable.
    WARNING: The safety ground brought by the mains power supply cable is generally too long and inductive to provide a proper earth ground against lightning surges. However, you can bond the camera ground to the local earth grounding point at the pole.
F Mounting pole:
  • In this example, the camera and the plastic, ungrounded enclosure are mounted on a conductive metallic pole. The pole acts as a grounding path between the grounding strap and the earth ground at the bottom of the pole.