Marsh Bellofram Diversified Electronics Division CMC Series AC Over Current Monitor - Marsh Bellofram - #1

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800.727.5646 atcdiversified.com Diversified Electronics CMC Series Current Monitors // CMC Series 239 A C Ov e r C ur r e n t M o n i t or The CMC Series is used to detect a motor jam up and give the equipment an opportunity to clear itself before going into a lockout and alarm mode. Control voltage is continuously applied to the CMC monitor. Upon application of the control voltage the Forward and Alarm Relays energize. When AC current is initially applied, the Inrush Time Delay is initiated to disable the over current sensor during the inrush period. (See 1 on graph). On over current the Forward Relay de-energizes and the unit has a 5 second dead band, then the Reverse Relay energizes for the selected time delay. then, the Reverse Relay de-energizes, rests for the Dead Band and the Forward Relay energizes completing one full cycle (See 2 on graph). After one cycle is complete the Forward relay remains energized if conditions have returned to normal. If an overcurrent remains, the unit will go through the same operating sequence as before until jam is corrected or the number of preselected cycles have occurred. The number of cycles that occur before lockout is field selectable from 1 to 9 cycles. to prevent the faults from accumulating and causing nuisance alarms, a Time Band is initiated upon sensing the first fault. Then, successive occurrences equaling the number of faults within the Time Band will cause alarm. The Formula for the time Band is 70 seconds x (Count-1) When the number of cycles reaches the pre-selected count, the Forward, Reverse and Alarm Relays lock into the de-energized state. (See 3 on graph) Reset is accomplished by pressing the reset button. The LED indicator glows when the Forward Relay is energized. The CMC series operates in the fail safe mode as the relays are energized in normal conditions. An External CT may be used to extend the range of the Current Monitor. \\\OPERATION MODEL NUMBER CONTROL RANGE ADJUSTMENT RANGE CMC-24-ASE-5 24 VAC 1.0 to 5.0 amps CMC-24-ASE-10 24VAC 2.0 to 10 amps CMC-120-ASE-5 120 VAC 1.0 to 5.0 amps CMC-120-ASE-10 120 VAC 2.0 to 10 amps \\\WIRING INCLUDES REVERSING RELAY & FAULT CONDITION COUNTER \\\SPECIFICATIONS CONTROL VOLTAGE 120 VAC, 50/60 Hz OVER CURRENT Inrush Delay 0.1 to 10 SEC, Adjustable (Forward and Reverse Operations) Alternating Delay 5 SEC, Fixed Reverse Operating Time 0.3 to 30 SEC, Adjustable Number of Fault Occurrences Selector Switch, 1 to 9 occurrences; Must occur within the Sampling Time. OUTPUT (3) Separate SPDT 10 Amp Relay Contacts, (1) Forward, (1 ) Reverse, (1) Alarm INDICATOR LED glows when Forward Relay is energized TEMPERATURE RATING Operate 32° to 131°F (0° to +55°C) Storage -49° to 185°F (-45° to +85°C) ENCLOSURE Style E: Surface Mount Lexan #8-32 Screw Terminals WEIGHT 20 oz.