With the increasing emphasis on energy efficiency and accountability in commercial office buildings, complying with regulations like Local Law 88 has become essential. The EASTRON MODEL SDM630 is a versatile sub-metering solution that offers accurate energy measurement for various applications. In this technical guide, we’ll walk you through the installation process of the SDM630 to ensure compliance with Local Law 88. Additionally, we’ll explore how to network multiple devices using Modbus hubs and internet gateways.
Before we begin, lets discuss the difference between three phase and single phase electric power.
Imagine a single water pipe delivering water to your home. This pipe provides all the water you need for things like drinking, cooking, and cleaning. Similarly, single-phase electric power is like having one “pipe” of electricity that powers your home or small businesses. It’s great for everyday uses like turning on lights, using appliances, and charging devices.
Imagine you have three different water pipes carrying water to power different things, like lights, machines, and computers. These pipes work together in a balanced way, making sure there’s a continuous flow of power. Similarly, in a three-phase electrical system, there are three “pipes” of electricity that power various devices, making the overall distribution of power smoother and more efficient.
Now to make things a tiny bit more interesting, there are two types of three-phase electric loads and they are called 3-wire and 4-wire systems.
To clarify the contrast between 3-wire and 4-wire electric systems and why it is important for sub-metering purposes, let’s break it down:
3-Wire Electric System:
Think of a 3-wire system like a simple path for electricity to travel. It’s like walking on a trail with three clear directions to go. In this setup, there are three wires that carry electricity: one for the power to flow in, one for the power to flow out, and one that’s like a helper to keep things balanced. For sub-metering purposes we only need to sub-meter two of the three wires.
4-Wire Electric System:
Imagine you’re in a bigger place, like a neighborhood, and you need more paths to get around. A 4-wire system is a bit like that. It has four paths for electricity. In this case, you have the same three paths as before, but there’s an extra one added, like a special lane for certain things. For sub-metering purposes, we need to sub-meter 3 of the four wires.
In a 3-wire system, it’s like having a simple way for electricity to go back and forth. It’s used in many homes for regular things like turning on lights and using appliances.
In a 4-wire system, that extra path (the fourth wire) is there to handle something special, like bigger appliances that need extra power. It helps keep things safe and makes sure those big machines can work properly without causing any problems.
So, to put it simply, a 3-wire system is like a straightforward path for electricity, while a 4-wire system is like having a little extra road to handle bigger stuff in a safe and organized way.
Think of your home’s electricity meter. It keeps track of how much electricity you use in kilowatt-hours (kWh). But what about when many things turn on at the same time, like when you start the washing machine, turn on the lights, and use the oven? This sudden increase in power use is known as the “demand.”
For three-phase loads, it’s like having three sets of appliances running at the same time. To measure the demand, you need to know how quickly power is being used, which is where kilowatts (kW) come in.
Imagine you’re filling a bucket with water. The rate at which the water fills the bucket is like the rate at which power is being used. This rate is measured in kilowatts (kW). If you’re filling the bucket faster, it means you’re using more water per second, just like using more power per second in electrical terms.
To measure the kW demand of a three-phase electric load, you need a special meter that keeps track of how much power is being used at any given moment. This meter calculates the kW demand based on how much electricity is flowing through each of the three “pipes” of power.
When you use a lot of power in a short amount of time, like when you start many machines together, the meter notices the increase and records the higher demand. This helps businesses understand when they use the most electricity and manage their energy use more efficiently.
So, just like keeping an eye on how much water you’re using, measuring the kW demand of a three-phase electrical load helps manage and control power consumption in a more balanced and cost-effective way.
The main difference is in how much power they can handle and what they’re used for:
In simple terms, single-phase is like a regular car that you use for daily commuting, and three-phase is like a heavy-duty truck that’s meant for hauling big loads. So, depending on what you’re powering, you might need the regular “car” power of single-phase or the heavy-duty “truck” power of three-phase.
Before starting the installation process, make sure you have the following:
Most tenant sub-meters are single phase wiring connecting office equipment and lighting systems. The diagram below illustrates how technicians should wire the SDM630 for single phase kW metering. Readers can access a link to this diagram on the store’s website by clicking here.
Utilizing Modbus communication to network multiple SDM630 devices offers several benefits:
The EASTRON MODEL SDM630 provides an effective solution for sub-metering applications in commercial office buildings. LC Associates helps you comply with Local Law 88 and improve energy efficiency. By following the installation steps outlined in this guide and utilizing Modbus networking with hubs and internet gateways, you can accurately monitor energy consumption and contribute to a more sustainable built environment.