(1985-1990)  During this period, company was engaged in designing and developing simple but innovative electronic instrumentation and controls that were custom built. We were trying to replace,or   trying to convert, physical phenomenon into reliable measuring signals, controls etc. Most of the designs were based on analog circuits and have gained a good knowledge and expertise in analog circuit design. Most of such analog design building blocks were not so reliable those days and one had to struggle to reduce electrical noise and design for EMI / EMC. This means we had to build our knowledge and expertise and sharpen our skill in analog design techniques.
(1990-1995)  The company was approached by a small OEM engaged in manufacturing of washing machine, to design and later to supply controllers for their products. Although initial quantity was about 30 pieces per month, we took it as a great responsibility. They increased the quantity to 250-300 pieces per month within two / three months (seeing the customer acceptability of these products). Very soon major players in this field approached us for designing and developing electronic washing machine controllers in order to replace their existing electro-mechanical timers. We, together with OEMS could add quite a lot of new features and value addition to their end products. Around the middle of 1995 there was slump in the white goods market due to some govt. policies, higher interest rate etc. The washing machine controllers that we manufactured for OEMs were not moving as it was earlier. We had to find same ways in order to cater our educated, experienced and skilled work force.
Our company was approached by two major OEMs engaged in the manufacture of air conditioners. We have designed and developed controllers for their newly introduced "Split airconditioners". Since we had lot of expertise in designing and developing reliable "analog controllers", this was an easy assignment. Market share of these OEMs increased very much and they demanded more quantity from us. Many new techniques on manufacturing and quality assurance were introduced during this period. Many of our major OEMs appreciated our efforts and also extended their suggestions.
(1995-2000)  Seeing this big jump in market share of their competitors, many other OEMs engaged in the manufacturing of airconditioning products, approached us for designing and developing controllers. These products had quite a lot of extra features which contributed in value addition
By this time PRESEVI got into "microcontroller" based designs from the mere analog with a humble start. Very soon most of the products were designed around microcontrollers. Our OEMs could deliver a truly "mechatronic" products to their customers and could attain increased market share. Presevi designed and developed many electronic controllers for chillers, Package air conditioners, humidity & temperature controllers, Precision air conditioning systems etc. We also introduced controllers with communication ports and BMS connectivity.
(2000-2005) During this period PRESEVI introduced documentation of all our procedures and obtained ISO 9001:2000 certification for design, manufacturing and service activities. The company has grown in size, knowledge, expertise and skill. We could also introduce AMF panels for motor generator sets, aircondition controllers for Military communication vehicles meeting strict IEC, EMI / EMC and IP 65 specifications. We also introduced BMS systems and several energy monitoring and saving controllers. In many organisations major energy consumption is by the air conditioning system and therefore PRESEVI introduced a damper operated economiser / free cooling controller (that will let outside air based on the enthalpy in conditioned space and ambient.
We also published documents and put them in our website www.presevi.in
  about the details regarding our controllers. Our customers could download these documents from our website and meet their requirements. The company concentrates in designing and developing high technology controllers and have got fairly good customer base.