LOW VOLTAGE INTERCONNECT WIRING

Depending on the thermostat required or selected, cooling only air handlers may utilize three to five low Voltage intercon- necting wires between the indoor unit, thermostat and the outdoor unit. Some thermostats do not require the use of the “C” (brown) connection. In this case, en- sure that any unused wires are insulated

Figure 1

�����������

���� � ����� �������� ��

�������������������������� ���

����� � �� � �����

 

� � ���� �

 

� �� ����

to prevent them from making contact with

������ �

�� ������

the junction box or other metal surfaces.

If the indoor unit has electric heat then a “W” connection is required between the thermostat and the indoor unit.

�� �����

 

�������

������ ���� ���� ��������

������������� � �����

��������

START -UP FOR WALL THERMOSTAT CONTROL

Refer to low Voltage interconnect dia-

Toggle Switch

 

gram Figure 1 for remote wall thermostat

 

controls.

 

NOTE: Apply power to the Condens- ing Unit’s crankcase heater for 24 hours before start up to boil off any liquid that may be present in the compressor.

1.After 24 hours, the compressor should be isolated by removing the connection at the “Y” terminal on the outdoor unit. Main power can now be applied to the indoor and outdoor units. A system elec- trical check can now be carried out.

2.Switch on the indoor Cassette unit and check that the fan cycles correctly.

3.On models 18-36, check that the motor- ized vane sweep functions correctly by toggling the function on or off, via the toggle switch on the side of the electri- cal box.

4.For units with electric heat, check the operation of the heat elements by switching the system to the heating mode and set the room temperature above the set point.

5.Ensure that the Condensing Unit start up procedure has been carried out as detailed in the corresponding installa- tion manual.

6.The compressor signal “Y” (disconnect- ed in step 1) can now be reconnected and main power applied to the outdoor unit.

CAC Cassette Evaporator

14

www.enviromaster.com

Page 14
Image 14
EMI CAC manual LOW Voltage Interconnect Wiring, Start -UP for Wall Thermostat Control

CAC specifications

EMI CAC, or Electromagnetic Interference Common-mode Current, is a critical concern in electronic device design and operation. It refers to the unwanted electromagnetic energy that can disrupt the normal functioning of electronic circuits, particularly in complex systems. EMI can arise from various sources, including power lines, radio frequency transmitters, and even other components within the same device.

One of the main features of EMI CAC is its dual nature. It can be both a source of interference and a metric to assess the integrity of electronic systems. The impacts of EMI are far-reaching, affecting communication signals, power supply reliability, and overall device performance. As technology progresses and devices become more compact, the likelihood of EMI issues increases, making it essential for engineers to develop effective solutions.

Several technologies are employed to mitigate EMI CAC in electronic systems. Shielding is one of the most common methods, involving the use of conductive materials to block electromagnetic fields. This can take the form of metal enclosures or coatings that prevent the escape of emissions. Another strategy involves the use of filters, such as ferrite beads and capacitors, which can suppress common-mode currents before they enter the sensitive parts of a circuit.

The characteristics of EMI CAC vary depending on several factors, including frequency, amplitude, and the specific environment in which the electronic devices operate. High-frequency EMI is particularly challenging due to its ability to penetrate enclosures and disrupt signals. Additionally, common-mode noise can often appear in differential signals, exacerbating the situation and making detection more difficult.

Achieving EMC (Electromagnetic Compatibility) is a major goal for designers dealing with EMI CAC. This involves not only reducing emissions from devices but also improving their immunity to external sources of interference. Effective grounding techniques and careful layout planning are crucial in minimizing EMI effects.

In summary, EMI CAC represents a significant challenge in modern electronics, with a need for advanced solutions to ensure device performance and reliability. By understanding its features, employing effective technologies for mitigation, and addressing its characteristics, engineers can create robust designs that thrive in the increasingly complex electromagnetic landscape of today’s technological world.