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Abstract-This study introduces the development of a sub meter at the Electrical Measurement Lab of BMS College of Engineering in Bengaluru India at a location that, constitutes one of the several nodes on a distribution feeder in the first floor of a seven storey building. The system, monitors the behaviour of various electrical parameters during the operation of different types of loads connected to the three phases of the node under consideration. The three phase voltages and currents are sensed in real time and by the use of efficient algorithms usingTMS320F28335 Delfino by Texas Instruments, evaluation of several electrical parameters at a sampling frequency of 20 KHz has been accomplished. An effective strategy using Arduino platform for dynamic data transmission to cloud storage and a web-based Graphic User Interface brings in the graphical visualization of the operational status of the loads and the consumption cost from any remote location. Several such units are planned at various nodes and the data of each would aggregate to measure the total consumption at the secondary of the distribution transformer feeding the building. A prototype of one such typical unit developed is presented here.Keyword-Sub-metering, Online Monitoring, GSM, Bulk Consumers I. INTRODUCTION Distribution companies provide electricity at different rates to several categories of consumers. Every state in India has different categories that cater to the needs of the business variety prevalent in their states. The common categories are domestic(residential),commercial(shops and offices) and industrial(manufacturing units) with rates being the lowest for residential consumers and highest for industrial consumers. There are separate rates for LT (Low tension) and HT(High Tension) categories. In India, LT supply is of 400 Volts for three-phase connection and 230 Volts for single-phase connection. High tension or HT supply is applicable for bulk power purchasers who need 11 kilo-Volts or above. Most bulk consumers (HT) are charged based on a two-part tariff as given by expression (1).Energy charges = Contracted demand rate p * Maximum demand + TOD p t dt + TOD p t dt + TOD p t dt + Penalty component(1)Where,p = charge per KVA of maximum demand= fixed charges. Maximum demand is 75% of contracted demand or recorded maximum demand, whichever is higher. TOD =time of day Tariff 6am to 6pm;TOD =time of day Tariff 6pm to 10pm;TOD =time of day Tariff 10pm to 6am. The consumer has to pay the fixed charges irrespective of the energy consumption. Heavy penalty is levied on the consumer on overshooting the contracted maximum demand. Also, different rates are levied for consumption during on-peak and off-peak periods. Surveys conducted at the premises of the college reveal that the peak demand, has been steadily on the rise over the years as shown in Figure 1. The contracted demand, as per guidelines given by the utility company[1],is 650KVA,heavy penalty is levied when this value of demand is exceeded and when the overall power factor drops below 0.9...