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K8AK-PM

K8AK-PM
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omRonThree-phase Voltage and Phase-sequence Phase-loss Relay K8AK-PM Ideal for Monitoring 3-phase Power Supplies for Industrial Facilities and Equipment. • Greater resistance to inverter noise. new • Monitor overvoltages, undervoltages, phase sequence, and phase loss for three-phase 3-wire or 4-wire power supplies with just one Unit. Switch setting for 3-phase 3-wire or 3-phase 4-wire power supply. •Two SPDT output relays, 5 A at 250 VAC (resistive load). Output overvoltages and undervoltages using separate relays. •World-wide power specifications supported by one Unit (switchable). • Output status can be monitored using LED indicator. A Refer to Safety Precautions on page 10. Refer to page 8 to 9 for commonly asked questions. Ordering Information List of Models

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Specifications Input frequency •Relationship of Mounting Distance between K8AK-PM Relays and Ambient Temperature (Reference Values) The following diagram shows the relationship between the mounting distances and the ambient temperature. If the relay is used with an ambient temperature that exceeds these values, the temperature of the K8AK may rise and shorten the life of the internal components. DIN Track Distance between products: d

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Note: 1. Do not connect anything to terminals that are shaded in gray. 2. Use the recommended ferrules if you use twisted wires. Wiring Example Operation Indicators •Overvoltage/Undervoltage and Phase Sequence/Phase Loss Operation Diagram Item *1 Over_Ry turns OFF when phase loss is detected. *2 L1 and L2 are also used for the power supply. If the voltage becomes very low, the indicator will turn OFF. *3 The indicator will flash once per second after an incorrect phase is detected and once per 0.5 second during the detection time. Note: 1. The K8AK-PMD output relay is normally operative. 2....

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NomenclatureFront •Indicators Item * The input across L1 and L2 is used for the internal power supply. Therefore, the power indicator will not be lit if there is no input across L1 and L2. •Setting Knobs Note: 1. Use either a solid wire of 2.5 mm2 maximum or a ferrule with insulating sleeve for the terminal connection. The length of the exposed current-carrying part inserted into the terminal must be 8 mm or less to maintain dielectric strength after connection. For 2.5 mm2 or For ferrules with smaller solid wires an insulation sleeve. Recommended ferrules Phoenix Contact • Al...

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•Input Connect to L1, L2, and L3 (for three-phase three-wire mode) or L1, L2, L3, and N (for three-phase four-wire mode), depending on the mode selected using pin 2 on the DIP switch. The Unit will not operate correctly if the DIP switch setting and the wiring do not agree. Make sure the phase sequence is wired correctly. The Unit will not operate normally if the phase sequence is incorrect. •Outputs Terminals 11, 12, and 14 are the output terminals for overvoltage (SPDT). Terminals 21, 22, and 24 are the output terminals for undervoltage, phase loss, and phase sequence (SPDT). * Use the...

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●Overvoltage The overvoltage knob (OVER) is used to set the overvoltage threshold. The overvoltage can be set to between −30% and 25% of the rated input voltage. Turn the knob while there is an input to the input terminals until the alarm indicator flashes (when the set value and the input have reached the same level.) Use this as a guide to set the voltage. The rated input depends on the model and DIP switch setting. Example: K8AK-PM1 with Pin 2 Turned OFF (Three-phase, Three-wire Mode) and Pins 3 and 4 Turned OFF (Rated Voltage of 200 V) The rated input voltage is 200 VAC and the setting...

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Checking Operation How to Measure the Operating Time Overvoltages Gradually increase the input from 80% of the set value. The input value will equal the operating value when the input exceeds the set value and the alarm indicator starts flashing. Operation can be checked by the relay output that will start after the operating time has passed. Undervoltage Gradually decrease the input from 120% of the set value and check the operation using the same method as for overvoltage. Example: For monitoring mode set to three-phase three-wire monitoring, a rated voltage of 200 V, and an operating...

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Load-side Phase Loss In principle, phase loss cannot be detected on the load side because the K8AK-PM measures three-phase voltage to determine phase loss. Overvoltage Detection When Only One Phase Exceeds the Overvoltage Set Value The K8AK monitors each of the three-phase voltages. This means an overvoltage is detected even if only one phase exceeds the set value. The same applies to undervoltages. Motor Load Phase Loss during Operation Motor load phase loss cannot be detected during operation. It can be used to detect phase loss at startup. Normally, three-phase motors will continue to...

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Warning Indications K8AK-PM Safety Precautions Be sure to read the precautions for all models in the website at the following URL: http://www.ia.omron.com/. Electrical shock may occasionally cause serious injury. Confirm that the input voltage is OFF before starting any wiring work and wire all connections correctly. Electrical shock may cause minor injury. Do not touch terminals while electricity is being supplied. There is a risk of minor electrical shock, fire, or device failure. Do not allow any pieces of metal, conductors, or cutting chips that occur during the installation process to...

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Precautions for Safe Use 1. Do not use or store the product in the following locations. • Locations subject to water or oil • Outdoor locations or under direct sunlight • Locations subject to dust or corrosive gases (particularly sulfurizing gases, ammonia, etc.) • Locations subject to rapid temperature changes • Locations prone to icing and dew condensation • Locations subject to excessive vibration or shock • Locations subject to wind and rain • Locations subject to static electricity and noise • Habitats of insects or small animals 2. Use and store the product in a location where the...

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