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I n s t a l l a t i o n & O p e r a t i o n M a n u a l
Innovators in Clean Air Technology | www.envirco.com
MDR16
MAC 10
®
Remote Mount Fan Controller
Regarding powering off the MDR16 and the ENVIRCO FFUs, there are some factors to consider regarding your AC wiring and entire power
switching design. If the MDR16 is controlling eight or fewer ENVIRCO FFUs, then there is nothing special to consider. If the MDR16 is
controlling greater than eight ENVIRCO FFUs and the system design requires operation with the automated control input, then the only way
to shut down the FFUs is to power down the MDR16 by placing a switch between the AC main connection and the MDR16.
Automation Control Input
The automation input is single-ended, so power neutral and signal common are connected internal to the MDR16. Connect the ¼”
insulated quick connects to your control input wiring. Connect the 0-10VDC control signal to the
Signal
connection. Wire the control signal
common to the
Common
connection.
The input presents a 21K ohm load to the signal source. Include the resistance when calculating a dropping resistor for 4-20mA operation.
A 511 ohm series 1% ¼ watt resistor is used to provide 500 ohm dropping resistance.
Motors
Connect all motors in parallel using a bus, star or combination wiring scheme. Use AWG 18 twisted cable. Provided with the MDR is a pack
of 50 self-splice connectors to implement the wiring. See the MDR16 Wiring Connections diagram for details.
Important to note: When
connecting larger numbers of FFU’s to the MDR16, please make sure to design and layout the EC Motor control wiring paths to
minimize the total length of wiring accordingly.