Global distribution of maternal causes of. death. A maternal death is defined as the death of a. woman while pregnant or within 42 days of. termination of pregnancy, regardless of the. site or duration of pregnancy, from any cause. related to or aggravated by the pregnancy or. its management.
There are two types of control systems namely: 1  Open loop control systems (non-feedback control systems) 2  Closed loop control systems (feedback control systems)
Different types respond to temperature, pressure, humidity, liquid levels, other controls, manual intervention and other things. Lets add a basic control system to a refrigeration system. First we need to know what loads there are to be controlled. The image on the left shows a small split system for a walk in cooler with 3 electrical devices; a compressor, condenser fan motor and evaporator fan motor. Those 3 electrical devices are represented on the ladder schematic shown below.