Specifications

149
NLUO PMC CONTRACTOR
SIGNATURE AND SEAL SIGNATURE AND SEAL SIGNATURE AND SEAL
maximum face velocity of 3.6 m/s. The condenser fans shall be direct drive axial type operating at not more than 1440
rpm variable voltage electric motors. 6 pole 900 rpm fan motors will be used for low noise level applications. The
Condenser fan speed control shall be based on head pressure of the refrigerant and not on ambient temp. The weight of
the Condenser Shall not be more than 50 Kgs.
2.5 Electronic Fan Speed Controller for Condenser fans
The condensers must be provided with electronically controlled fan speed controllers, the speed of fans must be
controlled based on Head Pressure. Pressure monitoring electronic switch must be suitable for application up to 12
Amps to take care of high motor amps.
2.6 Weight of the Indoor Units
The floor of the Server Room shall not be subjected to very high load due to the Precision ACs. The weight of the
Indoor units shall not be more than 200 Kgs, keeping in mind the strength of the floor in the DC.
2.7 Micro Processor Controller
• Each Air conditioners should have single microprocessor with following controls :
2.8 Control Type
The controls shall be a microprocessor programmable logic controller. the controls shall have separate indication of
operating modes (cooling, heating, humidifying and dehumidifying), alarm conditions (temperature high, loss of sensor,
compressor hp & lp, wet floor, no air flow and low humidifier water). the display and indication shall be visible on the
front without removing any external panels. local and remote alarms will be triggered if an alarm condition is reached. each
unit must be provided with large screen graphical display and additionally the controller must have feature of dual set point
programming.
• The control should have an auto-restart feature which will return the unit to normal operation resumption of mains
power.
• Automatic load / time and alarm sequencing function to be performed by the unit.
• Microprocessor must have output point for ON/OFF of motorized damper and must be suitable to be integrated with fire
point for unit shut off incase receiving signal from fire panel or fire detectors.