PC171

• Specially designed to protect large power transformers
• Self powered operation
• Liquid in Metal expansion type
• Ergonomically designed 270 deg dial for optimum viewing
• Complete Ambient temperature & Head compensation
• IP55 weather proof ventilated case, can be directly mounted on transformer
• Various Measuring ranges: 0-150°C, 20-140°C, 30-150°C, 0-120°C
• Measuring accuracy of 1% fsd.
• Stainless steel armour sheathed capillary of 5m, 6m, 10m, 12m can be provided
• Winding Temperature is measured using a special Thermal Imaging device which is specially designed for each transformer manufacturer
• Thermal imaging device accurately simulates the winding temperature gradient as a function of CT secondary current
• Since the time constant of the thermal imaging device is same as oil immersed transformer winding, the winding temperature is accurately tracked with respect to time.
• Switch and circuit testing facility provided from outside the case
• Maximum Temperature indicating pointer is provided
• All components are made of brass and non ferrous materials for reliable long-term performance
• No periodic site adjustments
• Upto four Microswitches or Mercury switches are provided for Alarm, trip, cooler fan/pump operation
• Mercury switches have 5A, 250V ac/dc rating
• Microswitches have better vibration resistance
• Microswitches are not sensitive to deviation from vertical mounting
• Also, use of mercury is banned in many countries
• Micro switches have 15A, 250V ac rating
• For higher dc rating, a Magnetic Blow Out (MBO) microswitch can be used which has rating of 3A, 250V ac/dc
• All circuits to earth are tested at 2500V, 50Hz for 1 minute