Modes of Operation

Either of the following modes are available as determined by the presence or absence of a cam switch which

is closed while the LTC is in transition.

Non‑Sequential Mode: The timer resets after a tapchange, regardless of voltage.

Sequential Mode: The timer resets only after the sensed voltage is back within the control band.

LED Indicators

The RAISE and LOWER LEDs light to indicate a voltage outside the band and a forthcoming tapchanger

operation as soon as the timer times out. With a slowly varying input, operation of the LEDs and initiation of

timing is very sharp with 0.2 V hysteresis. The LEDs have an expected life of 25 years.

Output Contacts

Two outputs drive a raise and lower motor starter relay. The starters may be any voltage up to 240 Vac. The

output contacts are rated at 2.5 A inrush current and will handle a NEMA size 1 starter or smaller.

Voltage Measurement Accuracy

The unit meets the requirements of accuracy Class 1 as defined in ANSI standards C57.12.30‑1977 paragraph

9.3 and C57.15‑4.2 when tested according to C57.15‑1986 paragraph 9.4.1.