Coolant Distribution Units (Motivair by Schneider Electric)

Overview

The brochure describes the CDU's role as decoupling facility water from the IT cooling loop and holding the secondary supply above dew point. Secondary supply temperatures run 55-113 F and above (ASHRAE W1-W5), and the secondary is kept above room dew point to avoid condensation. The range starts at MCDU-4U with 102 kW and continues with MCDU-10 at 210 kW, MCDU-25 625 kW, MCDU-40 1.2 MW, MCDU-45 1.5 MW, MCDU-50 1.7 MW, MCDU-55 2.1 MW and MCDU-70 2.5 MW.

The main lesson of the specification table is that capacity depends heavily on approach temperature. The MCDU-40 delivers about 1,213 kW at 90 F primary and 113/149 F secondary (25% PG) but only about 337 kW at 90 F primary and 112/122 F secondary. Nominal primary/secondary flow for the MCDU-40 is 280/240 gpm, and available pump head ranges from 15 to 51 psi across models.

Hardware includes redundant dual pumps with VFDs, dual (A/B) power feeds on most models, and leak and dew-point monitoring, with BACnet, Modbus, SNMP and Redfish supported. Capacities are rated with 100% water unless noted, and glycol or custom fluids change them. This is product data rather than a white paper, but it is useful for CDU catalog fields and approach-temperature derates.

Key points

1. Range: MCDU-4U 102 kW, MCDU-10 210 kW, MCDU-25 625 kW, MCDU-40 1.2 MW, MCDU-45 1.5 MW, MCDU-50 1.7 MW, MCDU-55 2.1 MW, MCDU-70 2.5 MW.
2. Secondary supply 55-113 F+ (ASHRAE W1-W5), kept above room dew point.
3. MCDU-40: ~1,213 kW at 90 F primary with 113/149 F secondary (25% PG), but ~337 kW with 112/122 F secondary.
4. MCDU-40 nominal flow 280/240 gpm; pump head 15-51 psi across models.
5. Redundant dual pumps with VFDs, dual A/B feeds on most models, leak and dew-point monitoring; BACnet, Modbus, SNMP, Redfish.
6. Capacities are rated with 100% water unless noted; glycol and custom fluids change capacity.

Using it in design

• Store CDU capacity in the catalog as a table over (primary supply T, secondary supply/return T, fluid) rather than a single kW, and compute available capacity at the project FWS/TCS temperatures.
• Warn when the design approach (secondary minus primary) is tight, since capacity collapses.
• Require secondary supply above dew point.
• Check pump head against the TCS loop pressure drop.
• Model pump redundancy and A/B feeds for Tier checks.

Who should read it

Mechanical designers and catalog owners selecting CDUs for liquid-cooled halls.

Related standards

• ASHRAE Liquid Cooling Guidelines (W classes)
• UL/CSA/CE

Publication details

Authors

Motivair

Publisher

Motivair

Year

2025

Document language

English

Source type

Manufacturer

Access

Free to read

Licence

Copyright retained; citation only — the publisher’s terms apply to the original document

Citation