TC-CDU-L200R In-Rack Liquid-to-Liquid CDU (200 kW · 6U)
Liquid-to-Liquid Coolant Distribution Unit · 200 kW · 6U · for single racks around 200 kW
English PDF · Free download · No form required

High-density GPU racks
How it is used
Separate the facility-water loop from the rack coolant loop through a rack-mounted liquid-to-liquid CDU.
Selection checkpoint
Confirm facility-water temperature, available pressure and secondary-loop pressure drop.
Illustrative architecture, not a customer installation or an installation drawing.
Overview
- In-rack L2L CDU: facility water or dry-cooler loop on the primary side, PG25 to the rack manifold and cold plates on the secondary side
- 200 kW rated, 5 °C approach, 320 LPM secondary flow, variable 20–100%
- 1+1 redundant pumps with auto switchover, dual-feed ATS, leak detection, coolant quality monitoring, 50 µm filter
- PID control; Modbus RTU / TCP for BMS / DCIM
- 19-inch rack, 6U, 482 × 870 × 265 mm, approx. 100 kg, IP55
- For single GPU racks around 200 kW (GB200 / GB300-class and similar)
Engineering fit
For single GPU racks around 200 kW (GB200 / GB300-class and similar). Delivers 40 °C secondary supply from 35 °C facility water; every 1 °C of warmer facility water cuts chiller energy by roughly 2–3 %. Pairs with ToneCooling cold plates, manifolds and hose assemblies from the same factory, validated end-to-end on one CFD model and one test bench.
- Single GPU racks around 200 kW (GB200 / GB300-class and similar), one unit per rack with an isolated secondary loop
- Retrofits where facility chilled water exists and each rack needs its own secondary loop
- Server OEM / integrator rack bundles, delivered with cold plates and manifolds from the same factory
- Phased AI-cluster build-outs that add capacity rack by rack
Key specifications
| Parameter | Specification |
|---|---|
| Rated cooling capacity | 200 kW |
| Installation | In-rack, 19-inch, 6U |
| Dimensions (W × D × H) | 482 × 870 × 265 mm |
| Weight | approx. 100 kg |
| Coolant | PG25 (25 % propylene glycol / water) |
| Power supply | 3-ph AC 380 V 50/60 Hz or 480 V 60 Hz |
| Dual-feed ATS | Yes |
| Power consumption | < 2.8 kW |
| Ingress protection | IP55 |
| Display | 7″ touch HMI |
Performance & control
| Parameter | Specification |
|---|---|
| Approach temperature | 5 °C |
| Primary liquid in / out | 35 °C / 45 °C |
| Secondary liquid out / in | 40 °C / 50 °C |
| Secondary rated flow | 320 LPM |
| Flow range | 20–100% |
| Pump head | 30 m |
| Redundant pumps, auto switchover | 1+1 |
| Control | PID, flow vs. temperature |
| Flow check | 60,000 × 200 ÷ (1030 × 3.9 × 10 K) ≈ 299 LPM; 320 LPM rated incl. margin (ρ in kg/m³, cp in kJ/kg·K; ΔT in K) |
Monitoring · interfaces · environment
| Parameter | Specification |
|---|---|
| Leak detection | Yes |
| Coolant quality monitoring | Yes |
| Secondary filter | 50 µm |
| Bypass online-replaceable filter | No (standard on in-row models) |
| Automatic refill | No (standard on in-row models) |
| Communication | Modbus RTU & TCP/IP (RS-485 / RJ45) |
| Operating environment | −10 to 55 °C, 5–90 % RH |
| Storage environment | −45 to 70 °C, 5–93 % RH |
| Connections | Primary in/out, secondary supply/return, power and comms at rear |

Note: rated at 35 °C primary inlet, 40 °C secondary supply, PG25; other conditions per selection table. Platform names indicate compatibility only and imply no endorsement or partnership. Specifications subject to change.
Documents and factory tests
Supplied: dimensional / connection drawing, P&ID, Modbus register map, flow–pressure-drop curve, selection table, user manual. Factory tests: pressure hold, leak test, flow resistance at rated flow, pump / ATS switchover, leak-sensor / coolant-quality / comms check; records ship with every unit. Combined cold plate + manifold + CDU report for full-rack projects.
Compare models in this series
| Model | Capacity | Rated flow | Size / height | English datasheet |
|---|---|---|---|---|
| TC-CDU-L35R | 35 kW | 120 L/min | 4U | ↓ Download PDF |
| TC-CDU-L50R | 50 kW | 160 L/min | 4U | ↓ Download PDF |
| TC-CDU-L100R | 100 kW | 160 L/min | 4U | ↓ Download PDF |
| TC-CDU-L120R | 120 kW | 190 L/min | 5U | ↓ Download PDF |
| TC-CDU-L150R | 150 kW | 240 L/min | 5U | ↓ Download PDF |
| TC-CDU-L200R | 200 kW | 320 L/min | 6U | ↓ Download PDF |
| TC-CDU-L250R | 250 kW | 400 L/min | 6U | ↓ Download PDF |
Frequently asked questions
What CDU capacity does a 200 kW rack need?
Size the CDU at 1.1–1.2× the cold-plate heat load. TC-CDU-L200R suits racks with roughly 166–181 kW on liquid; choose the next model up for higher loads.
What does a 5 °C approach temperature mean?
Approach temperature is the difference between secondary supply and primary inlet. With 35 °C facility water in, TC-CDU-L200R delivers 40 °C coolant. A smaller approach allows warmer facility water and more free cooling.
In-rack or in-row CDU?
An in-rack CDU serves one rack, suits phased builds and retrofits, and isolates faults per rack. An in-row CDU serves a row at a lower cost per kW and suits new liquid-cooled halls. ToneCooling offers both.
What water does it connect to?
Primary side: facility chilled water or a dry-cooler loop. Secondary side: closed PG25 loop with 50 µm filtration, cleaned at the factory and pre-filled on request.
Which protocols are supported?
Modbus RTU and Modbus TCP/IP are standard; the register map ships with the unit. Ask about other protocols when requesting a quote.
Lead time and test reports?
Standard units ship in 6–8 weeks. Every unit ships with pressure, leak and flow-resistance test records; rack-level packages include a combined cold plate + manifold + CDU report.
Get a CDU selection review
Send your rack or loop heat load, inlet temperature, coolant, required flow, pressure drop, power supply and available space. We will confirm the model and operating conditions.
Sample lead time: 6–8 weeks. Large primary-side production units: 8–10 weeks, subject to project confirmation.


