nVent SCHROFF 10130-325, Руководство пользователя

Страница: 11 / 51

Date: 2021/04/07 Page
: 11 of 47
2.2 Cooling capacity control
Controller Box
1 RJ45 connector Ethernet 5 Air inlet for differential pressure sensor
2 RJ45 connector RS485 (Modbus RTU) 6 Controller box rear view
3 Controller box front view 7 Door contact rear door/rear panel
4 Door contact front door
The LHX+ controller is located together with the differential pressure sensor in a 2 U /
19”
controller box (6) at the top of the cabinet.
The controller drives an electromechanical control valve in the water circuit to regulate the
flow of water through the heat exchanger as a function of the heat load. The control variable
is the data from the cold air temperature sensors.
In order to compensate for temperature stratification, the cold air temperature is measured by
2 temperature sensors at different heights. As control variable the temperature of the lower,
the upper or the average value of these temperature sensors can be used as a reference.
The air flow rate also has an influence on the cooling capacity, the controller can either set
the fan speed to a fixed value of 70 % -100 % or adjust it depending on the differential
pressure.