The PIROD PRLC-A tower lighting controller

PIROD tower company has been around for a while, thus there are likely many of these tower light controllers out in the field.  They perform a vital service in controlling and monitoring tower lights at remote transmitter sites maintaining a safe operating environment for aircraft and compliance with FCC rules.

PIROD was sold to Valmont in 2004, Valmont no longer manufactures or supports the product.  All is not lost, however, as XCEL Tower Controls does support it and parts are still available through them.

These units were fairly rugged, had good surge suppression on the incoming AC lines and are designed for easy access to service parts.

PIROD PRLCA tower light controller, WRKI Brookfield, CT
PIROD PRLCA tower light controller, WRKI Brookfield, CT

This particular controller is being installed at WRKI in Brookfield, CT.  We are adding toroid cores to the tower lighting circuits coming off of the tower because the last controller has been mostly destroyed by lightning.  It is a tall tower, on top of a tall hill, thus it gets struck by lightning many times over the course of a year.

WRKI tower, Brookfield, CT
WRKI tower, Brookfield, CT

The block diagram looks like this:

PIROD PRLCA block diagram
PIROD PRLCA block diagram

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The basic schematic looks like this:

PRCLA tower light controller schematic
PRCLA tower light controller schematic

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The entire manual can be found here, (medium sized .pdf) courtesy of John Brickley of EXEL tower controllers.