Grand LSS closed pure-water cooling systems

Use the equipment OEM’s limits to define pure water

Obtain the rectifier, drive or furnace supplier’s approved fluid specification, wetted-material restrictions and minimum/maximum flow requirements. ‘Pure water’ alone does not define an acceptable conductivity, pH, treatment chemistry or contamination limit. Grand’s claim that the system addresses corrosion, scaling and blockage is not proof that any site makeup water will be suitable.

Require a written water-quality schedule, treatment train and maintenance procedure. Agree conductivity measurement location, calibration and alarm limits, filter service, sampling and consumable replacement. Avoid copying numerical coolant limits from an unrelated electrical machine or another supplier’s manual.

Close the primary circuit and the external heat sink separately

Provide the equipment heat losses, permissible inlet/return temperatures, pressure drop and all operating modes. Ask for the pump duty, flow-distribution drawing and P&ID, including which parts belong to Grand’s package and which remain with the protected equipment. Confirm the allowable system pressure and fill, vent and drain arrangements.

If the selected LSS package uses a water-to-water exchanger, specify site secondary-water temperature, flow, quality and pressure, plus isolation between circuits. The reviewed family page does not establish that every LSS has the same exchanger or can tolerate an arbitrary site-water temperature. Obtain a duty selection and package drawing for the actual order.

Tie protection signals to the rectifier, furnace or drive

List the cooling conditions under which the connected equipment may start, must derate or must stop. Obtain the supplier’s cause-and-effect schedule and agree ownership of each permissive/trip. The official page mentions protection and communication but does not publish a safety architecture, latency or register list.

Confirm hardwired versus network signals, sensor-failure behaviour, communication loss, pump fault and high-temperature/low-flow responses. Assess the planned interruption and restart sequence with the equipment OEM. A general control function is not evidence of uninterrupted cooling after power loss or a full redundant system.

Plan access for water treatment and fluid maintenance

The original photo exposes internal service components, so ask for the current enclosure and access drawing before installation. Identify clearance for pump removal, vessel service, strainers and treatment components. Determine how sampling, draining and maintenance can be performed without introducing incompatible water or debris into the protected circuit.

Request spares and consumables for the exact supplied parts, with storage and replenishment requirements. ‘Compact’ website wording does not settle the installed access envelope or the time allowed before a thermal shutdown. Define planned downtime and any bypass/standby arrangements in the order.

Accept an integrated cooling loop, not a marketing label

Prepare an enquiry containing the OEM coolant requirements, connected heat losses, hydraulic resistance, secondary utilities and control interfaces. Request the issued selection, component list, drawing revision and inspection/test plan.

Agree witnessed hydraulic and thermal checks at stated conditions, fluid-quality checks and simulated alarm/communication behaviour. Neither capacity, stock nor a delivered reliability level has been independently established. This product brief records the actual LSS scope and the decisions needed to make a technically comparable purchase; it does not substitute for the final engineering design.

1. Approve coolant limits

   Obtain OEM requirements and issue the treatment/monitoring specification.

2. Define both fluid interfaces

   Close protected-loop duty and external heat-sink conditions.

3. Test control responses

   Agree flow/temperature/quality alarms, permissives and fault tests.