Caterpillar EMCP 4.3 / 4.4

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

• 
  Modbus Interface ZMB-3X
  From €399 ex VAT Configure Modbus Interface
• 
  Gateway ZGW-20
  From €899 ex VAT Configure Gateway
• Evaluation Gateway on a Raspberry Pi Edge with one device licensed
  Free Set up Evaluation Gateway on a Raspberry Pi

Models

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.^1, 2

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 enabled^1, 2

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 roles^1, 2

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.

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. Start with the public map.

   Caterpillar SCADA manual LEBE0010-00 (2010), sections 4.1 to 4.3 and Appendix A, is the best-effort starting point for both controllers. Use FC03: voltage register 100 is wire offset 99 (0x0063), frequency 102 is wire offset 101 (0x0065), and total real power 106 is wire offset 105 (0x0069), quantity 2. A one-based client uses 100, 102 and 106; a 4xxxx client uses 40100, 40102 and 40106. Compare these reads with the site display before expanding the point list.

4. Connect to the customer SCADA interface.

   LEBE0007-08 section 32 identifies the 120-pin connector: pin 100 Modbus +, pin 90 Modbus -, pin 101 reference. Read baud rate, parity and address under CONFIGURE / ALL SETPOINTS / NETWORK / RS-485 SCADA DATA LINK. Use one RTU client and follow the Cat termination and bias arrangement. For TCP, use the configured IP address on a protected controls network. The annunciator and engine CAN links are separate.

5. Decode the first readings.

   Read frequency with PDU 03 00 65 00 01: unsigned raw 0x1900 is 6400 / 128 = 50 Hz. Voltage at offset 99 is unsigned, 1 V per bit; synthetic raw 0x0190 is 400 V line-to-line. Read power with PDU 03 00 69 00 02: combine the first register as the high word of an unsigned 32-bit value, then subtract 2000000000 W. Synthetic bytes 77 37 7C 48 produce 125000 W, not a signed integer or Float32. Reject frequency or voltage outside the map’s valid ranges rather than treating unavailable codes as readings. Check against the display and test loss/recovery without issuing commands.

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.^1, 2

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.^1, 2