213-0772   24V High-Power Relay / Hydraulic Pump Relay (Main Relay)—Used to control high-load circuits in excavators, such as the main power supply, hydraulic pump, and preheating system.

I. Core Parameters

Part Number: 213-0772 / 2130772

Type: High-Power Electromagnetic Relay (Main Power / Hydraulic Pump Relay)

Coil Voltage: 24V DC

Contact Capacity: 60A (400V DC / 277V AC)

Replacement Models: AEP16024, AEP16024C02, 461-678

Terminals: 4 High-Current Bolt Terminals (2 for Coil, 2 for Contacts)

Appearance: Black square housing with metal mounting bracket and large connection posts

II. Primary Applications

Main Power Control (Battery Master Switch)

Power Supply for Hydraulic Pump Solenoid Valves / Proportional Valves

Glow Plug / Preheating Control

High-Power Cooling Fans, A/C Compressors

Engine Starting Control Circuits

III. Compatible Models (Excavators)

300 Series: 312C/312D/313D/319D/320C/320D/323D/324D/325D/329D/330C/330D/336D/345C

Engines: C4.4, C6.4, C7, C7.1, C9, C9.3, C13, C15, C18

VI. Common Faults and Diagnostics

Fault Symptoms: Complete loss of power to the machine, hydraulic pump failure, inability to preheat, no response during engine start-up

Diagnostic Methods:

Measure Coil Resistance: Approx. 80–120Ω (at 24V)

Power-On Test: A distinct clicking sound (indicating coil engagement) should be heard

Check Contact Continuity: Once powered on, the two contact terminals should show continuity (0Ω)