ABB ACS550-01-125A-4 ACS550 55 kW Frame R5 AC Drive

ABB ACS550-01-125A-4: 55 kW ACS550 drive in frame R5

For a 55 kW motor on a 400 V network, ABB’s catalogue offers the ACS550-01-125A-4 as a 125 A drive in frame R5. It is supplied as IP21 (UL type 1) unless the +B055 option selects IP54.

Typical applications are pumps, fans and constant-torque machines such as conveyors, where adjustable speed and simple commissioning matter more than special product engineering.

Technical specifications

Choosing between normal and heavy duty

At normal use the drive supplies 125 A for a 55 kW motor. For heavy-duty service it is rated 87 A and 45 kW. Pick the column that matches the load, not the kilowatt number alone.

ABB lists vector control, a swinging choke for harmonic reduction, a built-in category C2 EMC filter, built-in Modbus on EIA-485, coated boards and the FlashDrop parameter tool as highlights of the ACS550 series.

Wall space needed is 265 mm by 736 mm (box fitted) with 286 mm of depth, and the drive weighs 34 kg. Choose +B055 for IP54, which adds height (775 mm) and weight (42 kg).

Allow for 1940 W of losses in the cabinet. The drive moves 350 m3/h of air and is rated at 75 dB; recommended input protection is a 160 A gG fuse or a 175 A class T fuse. No brake chopper is built into frame R5; ABB offers external brake units for dynamic braking.

Environmental limits in the manual: relative humidity 5 to 95% without condensation, no conductive dust, chemical gas class 3C2 and solid particle class 3S2. Storage and transport range from -40 to +70 C.

Reading the ACS550-01-125A-4 order code

Ordering notes: the catalogue’s type key places options after the drive type. +B055 selects IP54, +0J400 deletes the control panel, +K451 and +K454 add DeviceNet or PROFIBUS DP, and +K466 adds RETA-01 Ethernet connectivity. Not all codes exist for every size.

The ACS550-01-125A-4 belongs to a long-running ABB series, so spare-part and replacement questions are common. Read the type designation on the drive label, compare it with the code shown here, and tell us the option codes printed after the plus signs. Those fit the panel, filter and fieldbus choices that the original drive carried.

Installing a frame R5 drive

Mount the ACS550-01-125A-4 vertically on a solid wall or panel back plate able to carry 34 kg, or 42 kg for the IP54 version, and keep the free space above and below that the user's manual specifies so cooling air can enter and leave. Because the drive moves 350 m3/h of air and gives off 1940 W, a cabinet installation needs a ventilation or cooling design that removes that heat; adding the drive to an existing panel without checking the heat load is a frequent cause of overtemperature trips.

Size the supply and motor cables according to the manual, use the recommended 160 A gG or 175 A class T input fuses, and keep motor cables separated from control and Modbus wiring. Shielded motor cable and correct earthing at both ends help the built-in C2 EMC filter do its job and reduce interference with nearby instruments.

Commissioning steps

Before the first start, check the network voltage at the incoming terminals and confirm the motor nameplate data: rated voltage, current, frequency, speed and power. Enter these values into the drive, choose the macro that best matches the application, and set acceleration and deceleration times suited to the machine. Since frame R5 has no built-in brake chopper, a load with high inertia may need longer deceleration times or an external brake unit to avoid overvoltage trips when stopping.

Run the motor first without load where the process allows, check rotation direction, then load it gradually while watching motor current and temperature. Save a copy of the final parameters; on sites with several drives of the same type, the FlashDrop tool mentioned above makes copying a proven parameter set quicker.

Operating in Gulf heat and dust

Pump stations, cooling towers and HVAC plant rooms in Oman can combine high ambient temperature with fine sand and, near the sea, humid salt-laden air. The manual permits 5 to 95% relative humidity without condensation and excludes conductive dust, so the installation should keep the drive in a clean, cooled electrical room or a properly ventilated enclosure. Where the drive must sit near the process in a dusty area, the IP54 option is the better starting point than the standard IP21 build, although it still needs cool, clean surrounding air.

High ambient temperature may reduce the current the drive can deliver continuously. Check the derating rules in the user's manual against the worst summer conditions at the site, not the design temperature of the building.

Maintenance for long service life

Keep the cooling air paths of the drive free of dust by cleaning at intervals matched to the site, more often in sandy or industrial locations. Inspect power terminals for discolouration and re-tighten as the manual advises, review the fault history in the control panel during routine visits, and follow ABB's maintenance schedule for components that age with running hours. For an older installation, keep the original type code and plus codes on file so a like-for-like replacement can be specified quickly.

Documents and quotation

Source documents: ABB’s ACS550 catalogue (3AFE64792857) and the ACS550-01 user’s manual. Browse AC Drives or the ACS550 range page for neighbouring ratings.

Please confirm before ordering: network voltage, motor current, duty class, IP rating and every plus code. The ACS550 is a long-established model, so check with us about current availability; Seven Star LLC, an independent supplier in Muscat, confirms stock and lead time at quotation.