EATON KD, HKD, KDC, CKD, CHKD K-frame molded case circuit breakers

Product Basic Core Information

Applicable models and configurations: The circuit breaker models are KD, HKD, KDC, CKD, CHKD, all of which are K-frame Series C, compatible with Digitrip OPTIM trip units, and support Powernet communication and/or regional interlocking functions; The OPTIM 750/1050 model is additionally equipped with auxiliary switches, alarm/lock switches, and other internal accessories need to be factory installed.

Rated and Application: Maximum rated voltage of 600 VAC, only applicable to AC scenarios; The maximum continuous current of the trip unit is three specifications: 125A, 250A, and 400A.

Certification standard: Complies with the US UL 489 standard and meets the (P1) requirements of international IEC 157-1.

100% rated operating model: CKD and CHKD models can operate continuously at 100% frame rating if they meet the following conditions: using 90 ℃ insulated wires and AL9CU terminals, installed in a 24 “high x 15” wide x 6 “deep enclosure, which does not require additional ventilation.

Supporting materials: Selection data, trip unit operation manual, wiring diagram and other materials (such as numbers 29-120K, 29C890, etc.) can be obtained from Eaton.

Full process installation specifications

The installation process includes pre inspection → accessory installation → fixation → wiring → protection → parameter setting. All steps must be carried out under power-off, and the key requirements are as follows:

Pre-check

Check the circuit breaker nameplate and system requirements, and confirm that the equipment is not damaged during transportation;

Before removing the circuit breaker cover, it must be placed in the trip or OFF position.

Installation of internal accessories

The rated plug and internal accessories need to be installed before fixing the circuit breaker, refer to the separate instructions for the accessories;

When reinstalling the cover plate, the threaded forming screws should be aligned with the original threads to avoid thread damage that may cause the cover plate to be loosely fixed.

Terminal installation

The wire terminal is fixed with a 7/32 inch socket wrench, with a torque of 6-8 lb. – ft. (8-11 N.m.);

When connecting aluminum wires, a suitable joint compound must be applied to prevent the terminals from overheating and causing accidental tripping or equipment damage.

Circuit breaker fixing

Surface installation should be drilled according to Figure 2-2, while panel installation only requires support holes at the load end. Concealed cover installation should be cut according to the dimensions shown in Figure 2-3;

Tighten the installation screws and washers firmly and not exceeding 28 lb. in. (3 N.m.);

The side of the circuit breaker is labeled with a wiring diagram of the accessories. If it is not visible after installation, it needs to be recorded in advance.

Wiring specifications

The control power supply is 24VDC, the trip unit load is 45mA, and the positive and negative poles must be connected to the corresponding terminals (No. 6+24V/No. 5 NEG). Reversing the connection will damage the electronic protection function;

The regional interlocking function requires the removal of the factory jumper between terminals 2 and 3. If it is not removed, it will be in a self interlocking state;

The four wire system requires the installation of a neutral current sensor at the neutral pole, arranged according to the dimensions shown in Figure 2-6.

Rated plug selection

The release unit needs to be matched with the corresponding rated plug, with specifications as shown in the table below:

The rated current of the trip unit can be selected according to the rated plug specifications

125A 63A、70A、90A、100A、110A、125A

250A 125A、150A、160A、175A、200A、225A、250A

400A 200A、225A、250A、300A、350A、400A

Terminal torque and protection

The torque of the wire/load terminal is determined according to the model, and the core specifications are shown in the table below:

Terminal model material applicable wire torque value (lb. in./N.m.)

TA300K/T300K Aluminum/Copper 3-350 AWG 275/31

TA350K/T350K Aluminum/Copper 250-500 AWG 375/42

TA402K Aluminum 500-750 AWG 550/62

Ladder type terminals (TA400K/TA401K, etc.) must be equipped with matching terminal shields and warning labels must be affixed to the upper part of the circuit breaker cover plate;

When wiring, it is necessary to maintain the original factory electrical clearance and creepage distance to prevent high voltage hazards.

Parameter Settings

Insert the Digitrip OPTIMZER handheld programmer into the programming port, set the INCOM address and trip unit current parameters;

Parameters can also be set through the circuit breaker interface module or IMPACC Series III software.

Manual operation method

The manual operation of the circuit breaker is achieved through the operation handle and PUSH-TO-TRIP button, without additional electric operation requirements. Key rules:

operating handle

There are three positions: ON, OFF, and release. The cover plate is engraved with ON/OFF, and the handle color bar is marked with red=ON, green=OFF (reset), and white=release;

Reset after tripping: simply turn the handle to the extreme OFF position. The reset button is only used to reset the fault indicator light and does not affect the mechanical reset of the circuit breaker.

PUSH-TO-TRIP button

Used to trigger the trip function and regularly test the flexibility of the operating mechanism;

Use a small screwdriver to operate, designed for mechanical triggering.

Safety principle: After the circuit breaker is tripped, it is strictly prohibited to close it again until the fault is identified and eliminated.

Inspection and on-site testing

This series of circuit breakers is designed for maintenance free use and only requires limited regular inspections and testing. All operations must be performed with power off. The core requirements are:

Daily inspection (4-1 to 4-7)

Cleaning: Use a lint free dry cloth/brush/vacuum cleaner to remove dust, do not blow debris into the interior of the circuit breaker, and investigate the source of pollution;

Mechanical testing: repeatedly turn the handle to ON/OFF to ensure that the mechanism is not stuck. If it is stuck, replace the circuit breaker;

Trip test: Press PUSH-TO-TRIP in the ON position and repeatedly trip reset close. If the reset fails, replace the circuit breaker;

Component inspection: Check the cover plate, handle, and base for cracks, paint peeling, and discoloration. If they are severely damaged, replace them;

Terminal inspection: Check that the terminals are not loose or overheated (discoloration/insulation melting/arc erosion). If there are no problems, do not tighten them randomly. If there is overheating, clean/replace the terminals and restore them to their original factory condition;

Installation component inspection: tighten loose installation screws;

Environmental inspection: Check for chemical corrosion, personal/fire hazards in the installation area.

General on-site testing

Execute according to NEMA standards and test the functionality of the Digitrip OPTIM trip unit using the OPTIMIZER handheld programmer.

Grounding fault trip unit test (mandatory requirement)

Regulatory requirements: According to NEC 230-95-C, the grounding fault protection system must undergo performance testing when newly installed, and written test records must be retained in accordance with UL 1053 requirements for inspection by inspection agencies;

Test power supply: Use a 0-24V low-voltage, high current AC source, and do not only test through neutral sensors (the trip unit is powered by phase current, not neutral current);

Trip test: Apply a current of 125% of the ground fault setting value to any phase, and the circuit breaker should trip within 1 second. The alarm indicator light (if any) should be activated, and the three phases should be tested separately;

Non trip verification:

Four wire system (with neutral sensor): current flows in from one phase, neutral sensor flows out, circuit breaker does not trip, and three phases are tested separately;

Three wire system (without neutral sensor): Current flows between any two phases without tripping the circuit breaker, and all phase combinations are tested separately;

Attention: On site testing is only for functional verification and cannot be used for on-site calibration. Temporary wiring for testing must be restored to its original state before power can be transmitted.

Safety Warning and Disclaimer

Core safety requirements: All installation, maintenance, and testing operations must be powered off and verified to have no voltage to avoid high voltage causing death/serious injury/property damage;

Material protection: Do not use corrosive commercial cleaning agents to prevent damage to nameplates and molded parts;

Nuclear application reminder: This instruction applies to general commercial scenarios, and additional instructions for nuclear facility safety related applications need to be obtained from Eaton;

Disclaimer: Eaton shall not be liable for any misuse or installation of the product. This statement is not exhaustive and does not provide any express or implied warranties. Eaton shall not be liable for any special, indirect, or consequential damages.