How should I wire the SPEEDCHECK-15/18 radar speed sign to my battery cabinet?

This article discusses how to wire the DC power feeding the radar speed sign into the battery cabinet for solar powered systems. This is important to take advantage of low voltage disconnect (LVD) protection.

Product applicability

The following products are discussed in this article:

  • SpeedCheck: SPEEDCHECK-15/18

In 2019 Q1 Carmanah changed to the SunSaver SS-10L charge controller for the SPEEDCHECK-15/18 radar speed signs. This allowed the signs to be directly connected to the load terminals of the charge controller, which provides low voltage disconnect (LVD) protection to help preserve the battery when it is in a low state of charge.

It is imperative to wire the radar speed sign power cable to the load terminals on the SunSaver charge controller. This will ensure the radar speed sign power is fed from the charge controller instead of directly from the battery.

SpeedCheck Solar Cabinet Wiring

SPEEDCHECK-15 Power Cable (inside junction box)

SPEEDCHECK-18 Power Cable (routed out from rear panel)

The system disconnect and reconnect voltages for the SunSaver are as follows:

  • Low voltage disconnect = 11.5V
  • Low voltage reconnect = 12.6V

Older systems that contain the ASC charge controller do not have low voltage disconnection (LVD) protection.

Systems that contain the StreetHub remote monitoring connectivity will have the cellular modem wired directly to the battery so it is able to continue to report in the event the battery goes into LVD.