Instruction Manual

OPERATION
The basic function of the Badger Meter
®
PRC-20 controller is to provide a relay output signal to external equipment to control
tank regeneration. Regeneration may be started automatically when a predetermined amount of water is measured by the
water meter, or may be manually started by a front panel or remote Start input. The batch size, up to 99,999,900 gallons, is
preset on the front panel, and the display counts down to zero. Regeneration is stopped either after a predetermined amount
of time expires, or a front panel or remote Stop input is received. The timeout, up to 9,999 seconds is set on the front panel.
The PRC-20 is programmed by the installer to operate either in Auto or Manual mode. In Auto mode, regardless of whether
regeneration was started by the batch count reaching zero, or by a Start input, the count will immediately return to the preset
amount and count down as pulses are received from the meter. Regeneration will end when the timeout period elapses,
or when a Stop input occurs. In Manual mode, the count will remain at zero, and regeneration will continue until a Stop
input occurs.
To avoid simultaneous regeneration of multiple tanks, a lockout signal can prevent a controller from starting regeneration at
the end of a batch. If a lockout is active when the batch counter reaches zero, or when a Start input is received, the controller
will remember to start regeneration as soon as the lockout signal is terminated. Furthermore, the running batch count can be
adjusted on the front panel as another method of avoiding simultaneous regeneration.
When power to the control is lost, the PRC-20 will store the running batch count in memory. If used in the Auto mode, and a
regeneration cycle had been started when power was lost, it will also store the time remaining in the cycle. The unit stores
these values in non-volatile memory, which requires no battery, and will retain these values.
When power to the control is turned back on, the unit will either continue from where it is left off when power was lost,
or it will automatically initiate a regeneration cycle. If the power up start input is disabled, the PRC-20 will simply continue
counting from the retained time value, and/or timing the regeneration cycle from the retained time value. If the powerup
start input is enabled, the PRC-20 will start a regeneration cycle, just as if the batch had counted down to zero, or the operator
had manually started one.
MOUNTING
The PRC-20 controller comes in a rugged, watertight polycarbonate enclosure intended for wall or panel mounting.
When mounting the unit select a location which has adequate ventilation, protection against mechanical shock and
accessibility for operation and service.
Operating Temperature: 32…122° F (0…50° C)
Operating Humidity: Up to 85% non-condensing
Wall or Panel Mount
1. Using the appropriate mounting hardware, attach the back part of the housing to the mounting surface.
2. Wire the unit according to “Wiring” on page 7.
Model PRC-20 with AR/t or RTR® Water Conditioning Control System
Page 6 April 2013