Caterpillar EMCP 4.3 / 4.4

Generator set controller family

The Cat EMCP 4.3 and 4.4 application guide documents customer Modbus RTU and TCP interfaces, measurement data, security levels and controller-specific feature differences. The controllers also expose start, stop, breaker and paralleling functions. This guide deliberately limits Edge to read-only monitoring and requires the installed controller level and software release to be recorded.

  • Modbus TCP
  • Modbus RTU

Generator set controller family

Compatibility

Documented customer Modbus interfaces

Caterpillar's exact family application guide documents the customer communication data link and Modbus RTU/TCP support. Edge can monitor an approved read-only set of points after the installed controller level and software are confirmed.

Cat EMCP 4.3 and EMCP 4.4 Generator Set Controls under application and installation guide LEBE0007-08; the separate EMCP 4.4 specification supports the 4.4 feature scope. Confirm exact controller level, generator set package, software and enabled communications. Do not write start, stop, mode, breaker, paralleling, protection, setpoint or output commands.

Connect it with

Route into Edge

When the controller Ethernet SCADA service is enabled and approved for monitoring

  • Modbus
  • Edge
  • Platforms
Generator set controller family
Interface
Gateway
Edge
Output
EMCP 4.3 / 4.4EMCP 4.3 or 4.4
Protected EthernetSegmented LAN
ZGW-20 GatewayHosts Edge locally
EpiSensor EdgeEdge Gateway
Customer platformMQTT · API · files
Modbus TCP
Protected Ethernet
Runs locally
Optional onward data
Use the customer communications interface and the register scope for the installed EMCP software. Keep the primary and accessory CAN data links and generator controls under the Cat system design. The customer-platform output is optional; Edge remains the local system of record.

When the customer RS-485 data link is assigned to the monitoring client

  • Modbus
  • Edge
  • Platforms
Generator set controller family
Interface
Gateway
Edge
Output
EMCP 4.3 / 4.4EMCP 4.3 or 4.4
Isolated serial interfaceApproved RS-485-to-host adapter
ZGW-20 GatewayHosts Edge locally
EpiSensor EdgeEdge Gateway
Customer platformMQTT · API · files
Modbus RTU · RS-485
Isolated serial
Runs locally
Optional onward data
Match the configured serial parameters and controller address, use an isolated interface, and do not confuse the customer data link with the RS-485 annunciator link. The customer-platform output is optional; Edge remains the local system of record.

Models

Download
ModelsInterfaceRoute into Edge
EMCP 4.3Customer Modbus interface with controller features defined in LEBE0007-08Record 4.3 identity and software; do not assume 4.4 paralleling features.
EMCP 4.4Modbus RTU on customer RS-485 and Modbus TCP on 10BASE-T Ethernet; paralleling feature setMonitor approved points only and leave paralleling control with the Cat system.
EMCP 4.1, 4.2 and 4.2BDifferent controller levels and feature setsOutside this family guide; use their own documentation.
EMCP remote display, HMI, supervisory and master panelsAccessories or higher-level systemsDo not treat accessory communications as the generator controller's customer Modbus endpoint.

Specifications

Caterpillar uses several internal and accessory data links. Monitoring uses the documented customer Modbus interface, not the engine CAN, accessory CAN, annunciator link or multiple genset data link.12

Family scope
EMCP 4.3 and 4.4 Generator Set Controls under LEBE0007-081
Customer protocols
Modbus RTU over half-duplex RS-485 and Modbus TCP over 10BASE-T Ethernet where supported and enabled12
Generator monitoring
Phase and average electrical values, frequency, kW, kVAr, kVA, power factor and energy counters2
Data-link boundary
Customer, accessory CAN, primary CAN, RS-485 annunciator and multiple-genset links serve distinct roles12
Configuration retention
Setpoints and software are stored in non-volatile memory2
Environment
Controller module -40 to +70 °C; display -20 to +70 °C; environmental sealed front face2

Interface

Documented measurements and integration boundaries for EMCP 4.3 / 4.4.

  • Generator phase voltage, current, frequency, kW, kVAr, kVA, power factor and accumulated energy where supported by the exact controller.
  • Engine speed, operating hours, battery voltage, oil pressure, coolant temperature and supported electronic-engine observations.
  • Warning, shutdown, alarm and diagnostic states plus generator and bus availability and breaker feedback as read-only observations.
  • Controller level, software release and generator set identity should travel with the point configuration.
  • Start, stop, mode, breaker, paralleling, protection, setpoint and output commands remain outside this guide.

Assessment

EMCP 4.3 or 4.4 with exact controller and software recorded; customer Modbus interface only and no operational writes.

InteroperabilitySupported with conditions
Caterpillar documents customer Modbus RTU and TCP interfaces, while exact point applicability depends on controller level, software and package configuration.12
AccuracySupported with conditions
Generator and engine measurements and electrical quantities are documented; sensor, CT and generator package configuration govern interpretation.12
SecurityLimited
Five configurable security levels and non-volatile settings are documented, but Modbus monitoring still requires network isolation and read-only client enforcement.2
ReliabilitySupported with conditions
Non-volatile configuration, diagnostics, protective functions and environmental limits are published; communications recovery needs site testing.12
RuggednessSupported with conditions
Temperature, humidity, vibration and sealed-front limits are published for the controller and display.2
ScalabilitySupported with conditions
Separate customer, accessory and multiple-generator links support larger systems, but each link's role and polling design must be preserved.12
LifecycleSupported with conditions
Caterpillar publishes a large exact-family application guide and product specification; controller software and generator package records remain necessary.12

Setup

  1. Confirm whether the installed controller is EMCP 4.3 or 4.4.

    Record the generator set serial, controller software release, package options and current Cat configuration before selecting points.

  2. Have the generator controls owner identify the customer Modbus port.

    Do not attach Edge to the primary engine CAN, accessory CAN, annunciator or multiple-genset data link.

  3. Build a read-only allowlist from the register information applicable to the installed controller and software.

    Exclude command, setpoint, protection and output registers even when they are documented.

  4. For TCP, use a protected controls network.

    For RTU, record address, baud rate, parity, termination, bias and isolation. Confirm the chosen port is not already assigned to another system.

  5. Compare generator voltage, frequency, power, run state and alarms with the EMCP display in a safe operating state.

    Test communications loss and recovery without issuing controls.

Common questions

Are EMCP 4.3 and 4.4 identical?
No. Caterpillar groups them in one application guide but distinguishes feature sets. Record the installed controller level and use only its applicable points and functions.1
Is the RS-485 annunciator link the Modbus connection?
No. Caterpillar lists the annunciator link and customer Modbus RTU link separately. Use the customer communications interface approved for SCADA or BMS monitoring.12
Can this Edge connection start or parallel generators?
No. EMCP controllers can perform those functions, but this guide publishes monitoring only. Operational control needs a separate Cat-engineered design and witnessed acceptance.12

Sources

  1. Cat EMCP 4.3 and 4.4 Generator Set Control application and installation guide LEBE0007-08 (opens in a new tab) Caterpillar
  2. EMCP 4.4 Generator Set Controller specification LEHE0135 (opens in a new tab) Caterpillar

Further reading

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