ABB REF542plus multifunctional protection and switch control device

Mechanical installation

Installation method: Supports panel embedded installation, 19 inch rack installation, or direct installation of circuit breaker cabinets, fixed with matching brackets to ensure stability and no looseness.

Installation steps:

According to the installation hole position fixing device, check the levelness (deviation ≤ 1 °).

Connect the grounding terminal to ensure reliable grounding.

Install the HMI panel, fasten it firmly, and avoid dust from entering through large gaps.

Wiring specifications

(1) Power wiring

The auxiliary power interface (X10) supports 24~250V AC/DC and needs to distinguish between positive and negative polarities. It is recommended to use 1.5mm ² single core copper wire.

The power circuit needs to be equipped with a 2A fuse to avoid overcurrent damage to the device.

(2) Analog input (X80~X88)

Current input: Supports CT (1A/5A) or Rogowski coils, three-phase current requires continuous wiring (such as L1 connected to X81, L2 connected to X82, etc.), and neutral wire connected to the common terminal.

Voltage input: Supports VT (100V) or resistive voltage divider, and the wiring of line voltage and phase voltage needs to be configured with corresponding devices (set through operating tools).

Wiring requirements: Analog cables need to be shielded, with the shielding layer grounded at one end and a distance of ≥ 100mm from the power cable to avoid electromagnetic interference.

(3) Switching input/output (X20~X41)

Switching input: 14 channels/module, supporting 24-250V DC, using optocoupler isolation, input current 2-20mA, distinguishing between "common terminal" and "signal terminal" during wiring.

Switching output: 8 channels/module, including relay output (capacity) 5A@250V  AC/DC）， Used to drive circuit breaker coils or alarm signals, the output contacts need to be connected in parallel with freewheeling diodes (when inductive loads are present).

(4) Communication wiring

RS485 interface (X60~X61): using shielded twisted pair, A and B wires are connected correspondingly, and the terminal needs to be connected to a 120 Ω matching resistor, with a maximum communication distance of 1200m.

Fiber optic interface (X62~X65): Glass fiber optic or plastic fiber optic, with a bending radius of ≥ 100mm, to avoid signal attenuation caused by excessive bending.