RAM DBS II
Refrigeration Solid State Starter
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LCD (Liquid Crystal Display) - A readout device in which each digit is formed by strips of liquid-crystal
material.
LRC (Locked Rotor Current) - The steady-state current taken from the line with the rotor locked (stopped)
and with the rated voltage and frequency applied to the motor. This is the motor manufacturer’s specified
current draw for a stalled motor.
NEMA - National Electrical Manufacturers Association.
Phase Loss - A condition when a loss of current or voltage has been detected in a polyphase circuit.
Phase Reversal - A condition when incorrect phase rotation has been detected in a polyphase circuit.
PLL - A phase-locked loop (PLL) is an electronic circuit that is constantly adjusted to match the frequency
of an input signal.
SCR (Silicon Controlled Rectifiers) - A semiconductor device that must be triggered by a pulse applied to
the gate before it will conduct.
Service Factor - An allowable overload; the amount of allowable overload is indicated by a multiplier which,
when applied to a normal FLA rating, indicates the permissible loading.
Stall Time - The maximum time at which the motor can be at locked rotor current without damage.
Step Ramp Mode - In this mode, the starter provides an initial current that is a percent of FLA. The current
is then ramped from its initial current setting to 500% over an adjustable time period. When the motor is at
full speed, the current is then determined by the motor load.
Thermal Capacity - The allowable amount of thermal energy that can be absorbed before damage may occur
to the motor.
Thermal Capacity Used - The calculated thermal capacity used by the motor.
Thermal Overload Level - The percentage of thermal capacity that has been consumed. This level is
calculated using the average of the 3-phase currents and the time that the current level exists. It is also
dependent on the Locked Rotor Current, Stall Time, and the FLA settings. NOTE: Heating from motor starting
current normally consumes a large percentage of the thermal capacity. Repetitive starts in a short time span
can exhaust the thermal capacity.
Trip - An undesirable condition that could result in damage to the motor. A trip condition will stop the motor
if it is running and not allow the motor to start until the cause of the trip condition is cleared.
Glossary
Glossary
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