Middex-ElectronicDC2Q ASBrushed DC Motor Speed Controller, Two-Quadrant, 24 V DC, 0-5 A with 6 A Peak, Adjustable Current Limit, DIN Rail

Product Description

What this part is

A Middex-Electronic DC2Q-AS speed controller for brushed DC motors. It is a DIN-rail mounted drive module: it takes a 24 V DC supply, drives a brushed DC motor at up to 5 A continuous with 6 A peak, and accepts digital inputs to run the motor in either direction. Current limiting is built in and adjustable.

Decoding the designation

In the Middex-Electronic scheme DC marks the brushed DC motor controller family and the 2Q states two-quadrant operation, meaning the drive controls torque in one direction of rotation while braking, and reverses through the direction input. The AS suffix identifies this variant of the module; the related DC2Q-ASX is a separate variant in the same family. Units frequently carry an additional firmware or configuration code appended after a slash, in the form DC2Q-AS/V55.11, which identifies the parameter set loaded at the factory.

What these specs mean in practice

A brushed DC motor changes speed with applied voltage, so a controller of this type works by switching the supply rapidly and varying the duty cycle. That gives smooth speed control from standstill upward while keeping the module efficient and cool enough for a DIN-rail housing. Digital inputs for clockwise and counter-clockwise running mean direction is commanded by a PLC output or a selector switch rather than by rewiring the motor.

The adjustable current limit is the specification that protects the machine. Motor current rises with load, so a current threshold detects a jam, an over-travel or a mechanical obstruction, and the adjustable reaction time from 1 to 700 milliseconds sets how long an overload is tolerated before the drive responds. A short reaction time protects a delicate mechanism; a longer one lets a motor draw its inrush and accelerate a high-inertia load without nuisance tripping. Setting that time is what makes the same module suit both cases.

The 5 A continuous and 6 A peak ratings suit small positioning and handling drives — conveyor sections, indexing tables, dosing and feed mechanisms — where a 24 V DC control supply is already present in the panel and a separate mains-fed drive would be excessive.

Published specifications

Function: speed controller for brushed DC motors
Operation: two-quadrant
Supply voltage: 24 V DC ±2 V
Motor current: 0–5 A continuous
Peak motor current: 6 A
Current protection range: 0–5 A
Current protection reaction time: 1–700 ms, potentiometer adjustable
Control signal: digital inputs for clockwise and counter-clockwise running
Motor type: brushed DC
Mounting: DIN rail
Order designation: DC2Q-AS

Quantity and configuration

Sold as 1 Pc — one controller module. The motor is not included, and no 24 V DC power supply is included.

Installation and setup notes

The module clips to DIN rail and terminates on screw terminals for the 24 V DC supply, the motor armature and the digital control inputs. Speed and the current limit threshold and reaction time are set on front-mounted potentiometers. Direction is selected by energising the appropriate digital input, and both inputs are driven from a PLC output or from dry contacts.

Interchange guidance

The DC2Q-ASX is a separate variant in the same Middex-Electronic DC2Q family and appears with its own configuration codes such as DC2Q-ASX/V72.11, so it is a related module rather than an identical article. Where a unit carries a configuration code after a slash, a replacement matches both the base designation and that code, because the code identifies the loaded parameter set. A direct replacement matches designation DC2Q-AS.