Datasheet

ManualsBrandsOmron Industrial Automation ManualsMonitoring RelaysVoltage Monitoring Relay, 1NC, 5A, 250V, 1.25kVA

New Product

Three-phase Asymmetry and Phase-sequence Phase-loss Relay

K8AK-PA

Ideal for 3-phase Voltage Asymmetry

Monitoring for Industrial Facilities

and Equipment.

• Greater resistance to inverter noise.

• Monitor voltage asymmetry, 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.

• One SPDT output relay, 5 A at 250 VAC (resistive load).

• World-wide power specifications supported by one Unit

(switchable).

• Relay status can be monitored using LED indicator.

Ordering Information

List of Models

Note: Three-phase, three-wire or four-wire and the input range are switched using a DIP switch.

* The power supply voltage is the same as the rated input voltage.

Single K8AK Monitors 3-phase Power Supply with 3 or 4 Wires

Monitoring Relays can be used to monitor 3-phase power supplies with 3 or 4 wires simply by changing DIP switch settings.

A Single K8AK Can Monitor a 3-phase Power Supply Anywhere in the World

Reduces Maintenance Parts Inventory

Refer to Safety Precautions on page 9.

Refer to page 8 for commonly asked questions.

For the most recent information on models that have been certified for

safety standards, refer to your OMRON website.

Rated input* Model

3-phase 3-wire mode 200, 220, 230, 240 VAC

K8AK-PA1

3-phase 4-wire mode 115, 127, 133, 138 VAC

3-phase 3-wire mode 380, 400, 415, 480 VAC

K8AK-PA2

3-phase 4-wire mode 220, 230, 240, 277 VAC

SW3 ON OFF ON OFF

SW4 ON ON OFF OFF

K8AK-PA1 SW2

ON P-N 138 V 133 V 127 V 115 V

OFF

P-P 240V 230 V 220 V 200 V

K8AK-PA2 SW2

P-N 277 V 240 V 230 V 220 V

OFF

P-P 480 V 415 V 400 V 380 V

Phase to phase voltage (3 wires)

Phase to neutral voltage (4 wires)

L1 L2 L3 L1 L2 L3 N

400VAC

230VAC

Summary of content (12 pages)

PAGE 1
New Product Three-phase Asymmetry and Phase-sequence Phase-loss Relay K8AK-PA Ideal for 3-phase Voltage Asymmetry Monitoring for Industrial Facilities and Equipment. • Greater resistance to inverter noise. • Monitor voltage asymmetry, 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. • One SPDT output relay, 5 A at 250 VAC (resistive load).
PAGE 2
K8AK-PA Ratings and Specifications Ratings Rated input voltage K8AK-PA1 Three-phase, three-wire Mode: 200, 220, 230 and 240 VAC Three-phase, four-wire Mode: 115, 127, 133 and 138 VAC K8AK-PA2 Three-phase, three-wire Mode: 380, 400, 415 and 480 VAC Three-phase, four-wire Mode: 220, 230, 240 and 277 VAC Input load K8AK-PA1: Approx. 4.4 VA K8AK-PA2: Approx. 4.4 VA Operating value setting range (ASY.
PAGE 3
K8AK-PA Specifications Input frequency 50/60 Hz Overload capacity Repeat accuracy Applicable standards Continuous input at 115% of maximum input, 10 s at 125% (up to 600 VAC). Operating value ±0.
PAGE 4
K8AK-PA Connections Terminal Diagram Control Output Relay output 250 VAC, 5 A (resistive load) 30 VDC, 5 A (resistive load) Input Voltages L2 L1 L3 L1 L2 L3 3-phase, 3-wire power supply Relay Output 11 12 14 _ _ Monitoring 3-phase, 3-wire Power Supply N _ _ 11 12 14 L2 L3 N _ _ 3-phase, 4-wire power supply or N L1 Monitoring 3-phase, 4-wire Power Supply Note: 1. Do not connect anything to terminals that are shaded in gray. 2.
PAGE 5
K8AK-PA Nomenclature ●Indicators Front Item Terminal block (See notes 1 and 2.) Asymmetry rate knob (ASY.) Meaning Power indicator (PWR: Green) Lit when power is being supplied* Relay status indicator (RY: Yellow) Lit when relay is operating (normally lit). Alarm indicator (ALM: Red) Asymmetry voltage error indicator The indicator flashes to indicate the error status after the input has exceeded the set value while the operating time is being clocked.
PAGE 6
K8AK-PA Operation Methods Connections ●Input N L1 L2 L3 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.
PAGE 7
K8AK-PA Setting Method ●Asymmetry The asymmetry rate is set using the asymmetry rate knob (ASY.) The setting range is 2% to 22% of the rated input. 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 make the setting. The rated input depends on the model and DIP switch setting.
PAGE 8
K8AK-PA Questions and Answers Q Q Checking Operation With the rated input voltage applied, gradually change the voltage to any one phase. The Unit will operate when the difference between the maximum and minimum voltage phases reaches or exceeds the asymmetry operating value. Asymmetry operating value = Rated input voltage × Asymmetry set value (%) Example: For monitoring mode set to three-phase three-wire monitoring, a rated voltage of 200 V, and an operating time of 5 s.
PAGE 9
K8AK-PA Safety Precautions Be sure to read the precautions for all models in the website at the following URL: http://www.ia.omron.com/. Warning Indications WARNING Indicates a potentially hazardous situation which, if not avoided, will result in minor or moderate injury, or may result in serious injury or death. Additionally there may be significant property damage. CAUTION Indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate injury or in property damage.
PAGE 10
K8AK-PA 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.
PAGE 11
Terms and Conditions Agreement Read and understand this catalog. Please read and understand this catalog before purchasing the products. Please consult your OMRON representative if you have any questions or comments. Warranties. (a) Exclusive Warranty. Omron’s exclusive warranty is that the Products will be free from defects in materials and workmanship for a period of twelve months from the date of sale by Omron (or such other period expressed in writing by Omron).
PAGE 12
OMRON Corporation Industrial Automation Company Authorized Distributor: Tokyo, JAPAN Contact: www.ia.omron.com Regional Headquarters OMRON EUROPE B.V. Wegalaan 67-69-2132 JD Hoofddorp The Netherlands Tel: (31)2356-81-300/Fax: (31)2356-81-388 OMRON ELECTRONICS LLC One Commerce Drive Schaumburg, IL 60173-5302 U.S.A. Tel: (1) 847-843-7900/Fax: (1) 847-843-7787 OMRON ASIA PACIFIC PTE. LTD. No.