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Safety PLC

Safety PLC means Safety Programmable Logic Controller. Their functions are similar with traditional PLC. But the different is that it has additional built in features that set them apart. They are built with redundancy to prevent the failure in the system. While standard and safety PLCs have similar appearances and functions, safety PLCs include additional redundancy and safety-specific capabilities, which are typically denoted by a bright color (yellow or red). The image was provided by Rockwell Automation. Not all control systems are impossible to avoid malfunction and device failure, so it is very important in some large processes or systems. Security In the event of a failure, PLCs' predicted failure modes lessen the degree of system disturbance. It is possible to reduce wiring complexity, time, labor expenses, and wire cabinet area by substituting safety PLCs for safety relays. A safety PLC also makes future system improvements simpler and less costly because, i...
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Difference between ELCB and RCCB

    ELCB နဲ့ RCCB နှစ်ခုစလုံးဟာ Protecting Device တွေပဲဖြစ်ပါတယ်။ ဒါပေမယ့် နှစ်ခုစလုံးဟာ မတူညီတဲ့ခြားနားချက်တွေရှိကြပါတယ်။ ELCB ====     ELCB ရဲ့ အဓိပ္ပာယ်က‌တော့ Earth Leakage Circuit Breaker လို့အဓိပ္ပာယ်ရပါတယ်။ ဒီ Safety Device ဟာ High Earth Impedance နဲ့ Electrical Installation တွေမှာ Electric Shock ကို ကာကွယ်ပေးဖို့အတွက်သုံးပါတယ်။      ELCB သည် Voltage Operates Device အမျိုးအစားဖြစ်ပြီးတော့ သူ့ရဲ့ ချိတ်ဆက်မှုတွေဟာ Phase , Neutral နဲ့ Earth Wire တွေပဲဖြစ်ပါတယ်။ ELCB ဟာ Main Earth Wire ကနေဖြတ်သွားတဲ့ Earth Leakage Current လိုမျိုး Electrical Fault ကိုသာ Detects လုပ်ပါတယ်။     ပထမပုံကိုကြည့်လိုက်မယ်ဆိုရင် ELCB ရဲ့ Normal Connection မှာဆိုရင် Current ဟာ Line ကနေ Neutral ကိုသွားနေမှာပါ။ အကယ် Fault အခြေအနေမှာ ရှိခဲ့မှာဆိုရင် သတ်မှတ်ထားတဲ့ Voltage ထက်များလာပါက Load က Trigger ဖြစ်လာပြီး Tripp Coil ထဲသို့  Current စီးဆင်းကာ Line နဲ့ Neutral ကြားက Current ကိုဖြတ်တောက်ပေးပါတယ်။ RCCB =====     RCCB ဆိုတာကတော့ Re...

Selection of the Power Supply

Today, I'm posting about the selection of power supply. This is just a tip and calculation. These estimated demands on the power supply, along with any additional load requirements for the particular power supply, including the minimum amount of time between surges (inrush), are used to choose the power supply. You will ask me that how to know that current, power and voltage of the electrical components. You can find it by reading instruction manual books or specification labels on the electronic components. 📝Although the majority of power supplies can operate at 100% of their rated capacity, it is advised to account for an additional 30%. However, other scholars argue that 20% should be included. What you plan to do with the gadgets in the future will determine this. This prolongs the life of the power supply and enables it to operate cooler and more efficiently. When i searched from the internet, there are two kinds of calculation. But they are not different. The...

Example of PLC ladder diagram for Filing and Heating Liquid in Tank

In the previous post, I wrote PLC program about Mixing and Heating process. Today, I'm going to write about Filling and Heating process in tank. It sounds like the same topic in previous post. Actually, it is different. We'll see the sequences and processes.  Here is the given sequences according to the Author : 1. Fill the tank up to 80%. When the tank is filled, turn ON the heater to raise the temperature up to 70 deg. 2. When this temperature is reached, turn OFF the heater & open the outlet valve. 3. When the level in the tank falls below 10%, close the output valve. In this situation, I do the ladder diagram via Sysmac Studio which is the product of Omron. I just remind you again, most of the control processes are used with Mitsubishi, Siemen and sometimes Delta's PLC due to cost effectively. I'm going to show you how it works with Sysmac Studio. In this case, I'm only using Name Tags. Before I'm talking about ladder diagram, I would like to tell about ...