FireLite SLC Wiring Manual — P/N 51309:R3  7/29/2019
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MDF-300 Wiring Diagrams Monitor Modules
5.5  MDF-300 Wiring Diagrams
Following is a wiring diagrams that depict NFPA Class B Initiating Device Circuits (IDCs) using MDF-300 Dual Monitor Modules.
5.5.1  Wiring a NFPA Class B IDC with an MDF-300
Connect the SLC wiring to the module terminals 1 (–) and 2 (+).
Use the rotary switches on the module to set it to the SLC address. Each dual module takes two addresses on the SLC. Circuit ‘L’ corre-
sponds to the address set on the rotary switches, which will be an even number. Circuit ‘H’ will automatically respond to the next higher 
address, which will be an odd number. Use caution to avoid duplicate addressing of modules on the system. Refer to “Setting an SLC 
address for a Single Point Module” on page 33.
Each IDC (H & L) is power limited to 230 microamperes @ 24 VDC.
The figure below shows typical wiring for a supervised and power-limited NFPA Class B IDC using an MDF-300-10 module.
• Refer to the Device Compatibility Document for compatible smoke detectors.
• See “Power Considerations” on page 63 for information on supervising 24 VDC power.
SLC-idcB3fdm1tph.wmf
Heat 
Detector
Manual 
Pull 
Station
SLC
MDF-300
Base +1 Address 
(IDC Circuit H)
Base Address 
(IDC Circuit L)
47K 
ELR
47K 
ELR
Manual 
Pull 
Station
Figure 5.14  Typical Class B IDC Wiring with an MDF-300