Zitron Commissions New Test Bench for FansThe Zitron test bench is the biggest in the world of its type. It has been built in compliance with standard 210-99 of AMCA (Association for air movement and conditioning) and is capable of reproducing any real tunnel situation, thus enabling the testing of all type of axial flow fans. It is a 98 m-long concrete structure with 600 mm-thick walls. The total tunnel volume is 5,145 cu m. The test bench has a testing capacity for up to 4 m-wide 1,600 kW axial fans. The opening and locking device of the test bench is carried out by means of remotely controlled hydraulic arms which activate a 8 m x 4 m hatch. Thirty 400 mm-diameter nozzles measure the flow, with 16 intakes on each static pressure side to measure the differential pressure. Seven settling means layers or levels with various meshes permit to achieve a stable flow. There are also seven setting chambers with an air vent area of some 52.5 sq m. One of these is equipped with nine total pressure taps distributed along the fan entrance. The auxiliary fan located at one end of the tunnel, just before the silencers, features a 2,400 mm diameter and a 250 kW output. It is 100% reversible. This room has an access hatch to insert the fan and do the maintenance. Panel silencers fitted to both sides of the test tunnel enable to attain a noise level of 55 decibels at both ends.All types of axial flow fan tests can be carried out in the test bench. The test make a complete analysis of the flow; pressure; power; current and voltage absorbed by the engine; real load vibrations; stall area; performance at any operating point; winding temperature; bearing temperature; and measurement of the fan sound power at the operating point in accordance with ISO 13347.Clients can supervise tests on site or by means of the real time monitoring cameras fitted inside the tunnel, with the results being transmitted through an internet connection.At the other side of the tunnel, the auxiliary equipment room makes it possible to carry out tests with capacities much greater than those performed to date on other test benches. The test fan variator has an output of 1,600 kW and 690 V (50-60 Hz), with sine wave and du/dt filters. The auxiliary fan variator has an output of 250 kW and is completely regenerative, which means it can supply 250 kW or absorb 250 kW, and an output voltage ranging from 380 V to 690 V and du/dt filter. Both transformers have an output of 1,600 KVA, an output voltage ranging from 1,000 V to 6,600 V and an operating frequency ranging from 5 Hz to 60 Hz. The room is fitted with measuring equipment racks with total and differential pressure transmitters, vibration and temperature sensors, stalling detectors and electrical measurement equipment. In the control room, the test process is carried out totally automatically, from start to finish. All this equipment ensures a measurement accuracy of over 99%. Visit www.zitron.com or click on their logo on the right-hand side. 26/05.