Key Advantages

• BALANCE LOADS - Ensure transformer loads are balanced.
• REGULATE VOLTAGE - Regulate line voltage by adjusting feeder voltage.
• REDUCE COSTS - Reduce power costs by providing minimum line voltage to the customer.
• PREDICTIVE MAINTENANCE - Deploy predictive transformer maintenance with intelligence.
•  MORE THAN AN LTC POSITION MONITOR - In addition to basic LTC tap position, the 1250-LTC monitors several additional important characteristics related to LTC movement. Programmable alarm options help utilities automate transformer maintenance planning. Check out these examples:
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• NEUTRAL TAP ASSURANCE - It is important for an LTC to pass through the neutral tap occasionally.If it doesn’t the reversing switch may become sticky and inoperable. The 1250-LTC has a programmable alarm that tells the utility if it has been too many days since the LTC has passed through the neutral tap.​
• TAP CHANGE ACKNOWLEDGMENT - The 1250-LTC can be programmed to close one of its relays upon completion of each tap change. This can be used as a feedback acknowledgment that the requested tap change was successful.​ If the acknowledgment isn't made, it can be a good indication that maintenance is required.
• ON-TAP DEVIATION MONITORING - Most LTC’s rotate about 9 to 11 degrees with each tap change. The 1250-LTC can measure in increments of 1/10th of a degree. A special feature of the 1250-LTC is its ability to monitor small discrepancies in tap position. A programmable limit can be set to give an alarm when the discrepancy in tap position reaches the limit. Inaccurate tap position can be an early indicator of wear in the LTC mechanism or possible impending failure.
• RUNAWAY LTC AVOIDANCE - If, for some reason, the LTC controller gets a faulty voltage reading, the LTC can run away in one direction; a serious condition that can effect transformer operation. The 1250-LTC has a programmable alarm that can be used to cut power to the drive motor if it detects too many tap changes in one direction.
• MAINTENANCE PLANNING - In the course of its life, an LTC may move up and down through the same few taps. As a result, these taps will have much more wear than the rest of the contacts. The 1250-LTC keeps a count of how many tap changes were made up to and down to every tap. This data helps utilities plan maintenance and replacement of the LTC contacts.

1. The 5-wire Syncro Transmitter is mechanically coupled directly to the transformer’s LTC drive mechanism.
   
   
2. Vital LTC position data is transmitted via AC signal to the LTC Position Monitor. The AC signal is 0-90 VAC and in-phase with the surrounding AC systems making it immune to noise.
   
   
3. Inside the substation control room, the signal from the Synchro Transmitter is interpreted by the LTC Position Monitor as an angle, which is precisely converted to a tap position by firmware.
   
   
4. The LTC position is fed to a central dispatch center via analog output signal through a Remote Terminal Unit (RTU).
   
   
5. Signals from a network of LTC Position Monitors can be fed into a utility’s SCADA system, providing remote LTC position information for an entire network of transformers.