The solar DC isolator switch allows for safe isolation of the solar array or battery. In many regions around the world, it’s even a legal requirement. This isolator switch, therefore, makes an important part of any solar photovoltaic (PV) system. Here is what it is and why you need it installed in your PV energy system.
Solar DC Isolator Switch
Let’s start with the isolator basics: A solar DC isolator switch is a type of DC-DC isolator that provides an electrical separation point between various circuits in a solar power system, but on the DC side.
The solar PV isolator switches works by cutting off electrical connection between the solar array and other components. This allows for maintenance or emergency disconnection. Being a manually
A battery isolator switch, on the other hand, would switch off the electrical link between the battery and inverter. Learn more about these two types of solar isolator switches below, including their installation tips and safety precautions.
Types of Solar DC Isolator Switch
A solar DC isolator switch or PV DC isolator switch is either a switch to isolate the panels or a switch for a solar battery or battery bank. Because each type serves its own purpose, it’s important to know the difference between them.
Solar Panel Isolator Switch
This switch is installed on the DC side of a solar system to separate the PV array from the AC inverter whenever required. The PV array isolator switch, as the device is also called, is often located close to the inverter, and properly sized for the array-inverter circuit currents and voltage.
The PV array DC isolator switch, just like any other direct current isolator in your solar system, allows you to conveniently isolate the solar panels from the rest of your system. This can be when you need to perform maintenance on the system or in an emergency and the power safely and quickly switched off.
For that reason, it’s a requirement by law to install a solar panel DC isolator switch in all PV systems, (particularly near the inverter), in many parts of the world. The switch should be clearly identified, and should also be easily accessible.
In situations where you have an outdoor isolator switch for your PV installation, it’s good practice to ensure you pick the right IP rating for the weather conditions. This means a switch that can stand up to the elements.
Solar Battery Isolator Switch
In a solar system, a battery isolator switch is installed to provide a means of disconnecting the battery from the rest of the system. In an RV or other vehicle that hasa solar power system installed, this switch is used to prevent the battery from draining when not in use.
A good example is when a camper is unplugged and stored for the winter months. By manually disconnecting the battery, the solar battery isolator switch ensures that the battery will not drain away all of its stored energy and ensuring it’s ready to use again when needed.
The solar DC isolator switch also provides a convenient way for campers to safely store their batteries without having to manually remove them from the system. The DC battery isolator switch can also be a switch that isolates the two batteries from each other, preventing them from draining power from each other.
DC to DC Charger Vs. Isolator Switch
Most often, users are faced with the dilemma of choosing between a DC-DC charger vs. isolator switch. Here is what you need to know about both options:
- A DC to DC charger typically works by regulating the charging current from the solar panels, which helps to protect the battery from overcharging.
- As soon as the battery is full, the charger will automatically shut off the charging process, protecting the battery from being overcharged.
- A solar DC isolator switch, on the other hand, serves to provide a physical barrier between batteries and the power source. Usually, it serves to segregate two batteries from each other, preventing any reverse current flow.
Depending on your needs, you may decide that a DC to DC charger is the right choice for your system. It provides protection from overcharging and can help to extend the life of your battery.
On the other hand, if using two batteries (main and auxiliary), a DC to DC s isolator switch may be more suitable as it offers full physical isolation between them.
Solar DC Isolator Rules
When it comes to using the solar DC isolator switch, there are few rulers that installers and users must observe. Some involve its installation while others concern the safety of the DC to DC isolator circuit. The rules are:
1. Your DC isolator should be adequately sized and its voltage rating equal to your specific system or greater. A lower voltage rating might lead to overloading and its associated risks.
2. Make sure that the IP rating of the isolator is suitable for use in your environment. Typically, a rating of at least IP65 is recommended. This ensures that your isolator is adequately protected against dust and water ingress.
3. The solar DC isolator switch should always be installed in an accessible area. This ensures that it is easy to reach in case of an emergency or during system service.
4. The isolator should have its own enclosure, which helps protect it from mechanical and environmental damage, especially if an outdoor isolator switch.
5. To ensure the longevity of the PV array DC isolator, make sure to inspect it regularly and replace it when necessary.
The solar DC isolator switch is a vital component of any solar system. It helps to ensure safety when working on, or even around a solar system. Before installing the switch, make sure you choose the right type for your system and keep in mind the safety rules that come with it.