Not every drive needs to survive a sandstorm. Most pumps, fans, and conveyors in a plant live somewhere much less dramatic: inside a cabinet, in an electrical room, behind a guard - indoors, protected, and never touched by dust or rain. For that majority of installations, the AT24 UB base line is built to do one job very well: control the motor reliably, communicate cleanly with the rest of the plant, and take up as little panel space as possible, without charging you for outdoor-rated hardware you'll never need.
One drive platform, one enclosure rating (IP20), one power range from 0.75 to 500 kW - the AT24 UB base line is the default choice whenever the installation is indoors and the job is standard pump, fan, or conveyor duty.
Key specifications
The table below covers the numbers that matter most when you're sizing and specifying a drive for a cabinet-mounted application.
Table 1. AT24 UB - key specifications (base line).
Compact by design
Panel space is never free, and the AT24 UB line is built around that constraint. At the small end, a 0.75 kW drive is under 90 mm wide - narrow enough to line up several units side by side in a control cabinet. Even the largest frame in the line, the 500 kW model, stays within a footprint sized for its output class rather than over-built for it.
Figure 1. Enclosure width across the AT24 UB power range - frame size scales with power, not beyond it.
Control that matches the load
The base line runs the same three control methods used across the wider AT24 UB family: open-loop (sensorless) vector control for most standard pump and fan duty, closed-loop vector control when a feedback encoder is fitted and tight speed accuracy matters, and simple scalar V/f control for basic constant-torque applications that don't need vector performance.
- Closed loop (with encoder feedback): ±0.1% speed accuracy - suitable for precise process control.
- Open loop (sensorless): ±10% of nominal motor slip - accurate enough for the great majority of pump, fan, and conveyor applications, with no encoder wiring to install or maintain.
Six acceleration/deceleration profile shapes (S-type, EL-S-type, U-type, reverse U-type, linear, and cubic) and a 0.1–4000 second ramp range cover everything from a gentle process start to a fast-response conveyor stop.
Connectivity: built in, not bolted on
Every AT24 UB drive ships with RS-485 (Modbus RTU) and Wi-Fi through a built-in web interface as standard - no separate communication module required to get either one running. Two option slots are available for anything beyond that baseline.
Table 2. Standard I/O and available expansion modules.
In practice, this means a technician can configure or clone parameters between drives over Wi-Fi from a phone, while the plant's SCADA or PLC talks to the same drive over Modbus RTU - or, with the EXT24_EHT module, over Ethernet with Modbus TCP/IP.
Protection that doesn't need a bigger enclosure
IP20 doesn't mean unprotected - it means the protection is built into the control logic rather than the box. The drive continuously monitors both the motor and itself:
- Motor protection: overload, underload, overcurrent, phase loss, current imbalance, encoder open-circuit, torque limit, and max/min speed limits.
- Drive protection: overload, overcurrent, power-switch overheating, DC-link over/undervoltage, output short-circuit to ground, and RS-485 communication-loss detection.
A braking chopper is built in up to 37 kW, and a DC-link choke is built in from 280 kW upward - the components most installations need are already inside the enclosure, not on a separate accessories list.
Need help sizing an AT24 UB drive for a specific motor and application? Send us the nameplate details and duty cycle - we'll confirm the right frame size and options.
Request a datasheet or a formal quote for the AT24 UB base line.
