These units can monitor parameters such as temperature and humidity or contact closure inputs and automatically generate an email alarm when temperature high or low limits are exceeded. Some also have relay outputs that can be used to activate a local siren, lamp or even cooling fan. They are self contained units that do not require any software running on a PC to operate. They are simply connected to your LAN, and an IP address is assigned either manually or automatically by your router. You can then access and configure using any web browser. With port-forwarding you can access from the internet.
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