Installation guide

Network Connection

MAC-4R panels are connected together for data communication over a twisted-pair cable. The twist-

ed pair may be shielded or unshielded. It should be noted that shielded data cable is not required.

Termination for this data line is via J1 terminals 5 and 6. It is not necessary to observe polarity for

data line hook-up.

If the data line is shielded, the shield should be terminated to J1 terminal 4. The shield wire should

only be terminated at only one end of each wire segment. Also note that terminal J1 pin number 3

connects to earth ground. This connection must be made to insure the RTU PC board has the prop-

er surge discharge path. It is recommended that the terminating resistor if required be installed as

shown in the diagram below to avoid being shorted over years of service.

Connecting Power

The MAC-4R can be powered through an AC transformer or DC power supply. The main power leads

are connected to J1 terminals 1 and 2. If using a DC power supply the positive lead needs to be

wired to terminal 1 (top) and the ground to terminal 2. The base draw of the control panel with nothing

connected except the power lead is 150ma. 50ma would be added per reader, 15 ma per input, and

40ma per output. When sizing the power supply provide 1 amp per controller. The PWR-24 is a 24

VDC power supply rated at 2.5 amps. It has enough power for (2) MAC-4R controllers.

Panel Grounding

The MAC-4R panel should be grounded by connecting the J1 terminal 3 to earth ground. When

mounted in a standard MAC-4R enclosure box, there is a ground lug located at the bottom middle of

the box. The PC board should be connected to this ground lug. The installer should always insure

the enclosure box is earth grounded at the nearest building ground point. Earth grounding the

enclosure provides a discharge path for power surges and ESD. An electrical circuit ground is not

an acceptable ground path. The ground should be to a ground rod, building steel or other true

ground source. The ground wire should be min 12 AWG wire and be kept as short as possible. con-

necting power to the MAC-4R.

REV 2.0