| Model | Image | Type | aaaaa |
| Model 171 |
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Under Current Monitor | The Model 171 is an AC current monitor for detecting undercurrent conditions. The monitor contains a proprietary microcontroller-based circuit monitoring current passed through an internal shunt resistor and driving an electromechanical SPDT relay. Two status lights are provided to indicate relay status, fault condition, and timing. An adjustable trip delay is provided to prevent nuisance tripping and an adjustable restart delay has been provided for applications requiring a delay to start an additional load. |
| Model 173 |
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Over/Under Current Monitor | The Model 173 AC Current Monitor is a single set-point AC current monitor. It can be used to detect either over current or under current, depending on whether the set-point is set above or below the input current. An LED indicator illuminates whenever the current is above the set-point. Two versions, either of which can be connected to 120 or 240 VAC, are available. One for current ranges up to 5 amps, the other for applications from 5 to 25 amps. For currents above 25 amps, matching CTs are available. The Model 173 is not frequency sensitive and can be used on AC currents from 40 to 400 Hz. The compact housing is surface mounted with 1/4 in. quick connect terminals provided for input and output connections. |
| Model 1732 |
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Over/Under Current Monitor | The Model 1732 AC Current Monitor is a single set-point current monitor. It can be used to detect either over current or under current, depending on whether the trip point is set above or below the input current. Dual LED indicators on the front or top of the unit give a clear visual reference for a fault condition. The Model 1732 generates its operating voltage from the monitored current line, so no external power supply is required. A current greater than 25 amps is needed to energize the internal relay. Momentary current above 150 amps will not damage the unit, however, the maximum current set-point is 150 amps. The Model 1732 is not frequency sensitive, and can be used on AC currents from 50 to 400 Hz. |
| Model 27 |
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TRUE RMS Over & Under Current Monitor | Model 27 True RMS Current Monitor has a display that shows the current with an accuracy of +/- 0.5%. The display is updated every second and re-initialized every 30 seconds. Model 27 has a rotary encoder with switch on the unit. By pressing the encoder switch for more than 5 seconds, the unit will enter the setup mode. This unit has a user selectable relay option for High-Low or DPDT. It can also be user-selected to energize on fault or de-energize on fault. The user can select automatic or manual restart on the Model 27. The SG version of the Model 27 has silver with gold flash contacts for low current applications. Model 27 True RMS Current Monitor can be either calibrated using a True RMS Multimeter or can be restored to factory defaults in the field. |
| Model 272 |
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3-Phase Current Unbalance Detector | The Model 272 3-Phase Current Unbalance Detector monitors 3-phase lines to detect an unbalanced current. It can also monitor three separate single phase lines for equal current levels. The percentage of unbalance is adjusted from 2% to 25% by adjusting a front panel control. An unbalance greater than this setting energizes the relay. An adjustable trip delay of 0.5 to 10 seconds is also provided. For optimum performance, operating currents should be kept in the 1 to 5 amps range. However, zero current on each phase is considered to be a balanced condition. Continuous currents, up to 10 amps per phase, will not damage the unit, nor will current surges up to 40 amps for 2 seconds. The contacts are automatically reset when the unbalanced condition is corrected. |
| Model 273 |
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Single Phase Over/Under Current Monitor | The Model 273 Single Phase Current Monitor is a single set-point sensor. It can be used as either an over current or under current sensor, depending on the contacts used. This device can directly monitor AC currents in the range of 0.5 to 5 amps: or 2 to 10 amps, 50 to 400 Hz. Matching transformers are available to extend the use of the monitor to most any range. The current being monitored can be of any voltage, up to the rating of the socket. An LED indicator is provided to show when the relay is energized. The Model 273 is available for either 24 VAC or 120 VAC supply voltages. |
| Model 2734 |
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Over Current Sensitive Relay | The Model 2734 Current Sensitive Relay monitors a single-phase AC current for an over-current condition. A top-mounted current transformer (CT) provides complete isolation from the control voltage as well as easy installation. Operation begins when the current being monitored rises to 10% of the trip setting, which initiates the start-up delay. When the delay expires, over-current sensing begins. In the AUTO mode, the Model 2734 resets when current drops below the trip setting. In the MANUAL mode, the unit must be reset by momentarily switching to the AUTO mode, and back, after the current fault is cleared. The TRIPPED LED indicates the output relay status. Current must drop below 10% of the trip setting for the start-up delay to restart. The standard model operates in a non-failsafe mode; if control power is lost, over-current detection is lost. A failsafe option is available, fixed or switchable. An adjustable dead band option is also available. |
| Model 274 |
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3-Phase Over Current Monitor | The Model 274 3-Phase Current Monitor is designed to monitor all legs of a 3-phase line, and can also be used to monitor three individual single-phase lines. The output relay will energize on an over-current condition on any one of the 3 monitored lines. Two indicator lamps are provided to show when an over-current condition exists and when the output relay is tripped. An adjustable trip delay of 0.2 to 20 seconds is provided to reduce nuisance tripping. Matching current transformers are available to extend the range of the device to most any range up to 1,000 amps. The Model 274 is offered in either manual or automatic reset models. An external power supply of 24, 120 or 230 VAC powers the device. |
| Model 2742 |
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3-Phase Over/Under Current Monitor | The Model 2742 3-Phase Over/Under Current Monitor is designed to monitor the current level of a 3-phase line or to compare the currents of three single-phase lines. The Model 2742 is factory-set as an over-current monitor; that is, if one or more current inputs rises above the trip level, the internal relay will de-energize. Adding a wire between the UNDER CURRENT terminals on the case will cause the Model 2742 to sense a decrease of one or more current inputs. An adjustable trip delay of 0.2 to 20 seconds will prevent nuisance tripping. The current trip point is adjustable from 1 to 5 amps, and matching current transformers are available to extend the current range of the monitor. The Model 2742 will automatically reset when the current fault is corrected. An external manual reset can be added by installing a normally closed switch between the terminals marked RESET. |
| Model 2744 |
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3-Phase Over Current Monitor For Motor Jams | The Model 2744 3-Phase Over Current Monitor is designed to monitor the current level of a three-phase line or to compare the currents of three single-phase lines. If one or more current inputs rises above the trip level after the start delay has expired, the internal relay will de-energize. An adjustable start delay of 5 to 15 seconds will prevent nuisance tripping on start up. The current trip point is adjustable from 1 to 5 amps, and matching current transformers are available to extend the current range of the monitor. The Model 2744 will automatically reset when the current fault is corrected. An external manual reset can be added by installing a normally closed switch between the terminals marked RESET. |
| Model 275 |
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Single Phase Over Current Monitor | The Model 275 Single Phase Current Monitor is designed for monitoring alternating current in the range of 1-5 amps, at 50 to 400 Hz. The Model 275 provides a contact transfer when the set current level is exceeded for a period longer than the time delay. The OVER-CURRENT indicator illuminates immediately. After the time delay, the TRIPPED indicator lights and the relay contact transfers. This device can directly monitor AC currents in the range of 1 to 5 amps; 50 to 400 Hz. Matching transformers are available to extend the use of this monitor to most any current range. The Model 275 is available with automatic or manual reset. Operating power is supplied by separate 24 or 120 volt power supply. |
| Model 279 |
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DC Current Monitor | The Model 279 DC Current Monitor is a single set-point DC current monitor. It can sense either 1-10 Amps DC (24VAC or 120VAC) or 0.1-1 Amps DC (120VAC). The units have an input frequency of 50/60 Hz. The standard version, the 279B, has a screwdriver adjustable trip and hysteresis setting on top of the device. The hysteresis setting adjusts from 0% to 100%, and can be set fully clockwise for manual reset operation. A remote adjust version, the 279C, has a remote trip adjustment and a remote reset button. An LED indicator is provided on both versions to indicate when the relay is energized (current above the trip setting. ) |
| Model 2722 |
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Current Unbalance Detector | The Model 2722 Current Unbalance Detector is designed to monitor 3-phase AC current (or compare three single-phase AC currents). A solid-state electronic sensing circuit drives an internal DPDT relay which energizes during normal, balanced conditions. An unbalanced condition will cause the relay to drop out. The Model 2722 accepts current inputs up to 5 amps and will consider zero amps as balanced (relay stays energized), making the device suitable for use with 3-phase heaters. The Model 2722 has adjustments for percent of unbalance and time delay before tripping. It will automatically reset upon restoration of correct current balance, or a normally-closed momentary switch can be connected for a manual reset. External CT’s can be used to extend the operating current range. |
| Model 2732 |
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Single Phase Over/Under Current Monitor | The Model 2732 Single Phase Current Monitor is designed to continuously monitor single-phase AC current. It consists of a solid-state sensing circuit driving an internal electromechanical relay. The Model 2732 has two operating modes: over-current sensing or under-current sensing. The operating mode is selected by means of a slide switch on the monitor. When operating voltage is applied, and the current level is correct according to the operating mode, the relay will energize. A fault condition will cause the OVER/UNDER LED on the monitor to illuminate, and the trip delay will begin. If correct current is restored, the relay remains energized. If current is not restored during the delay period, the relay will de-energize and the red TRIP indicator will illuminate. The Model 2732 has three reset configurations: automatic, manual (add jumper), or manual remote (add switch). The standard model, as provided, will reset automatically. |
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