Emerson MRLDS Powering the Gateway Board, Wire Connections, Input Voltage, Three-Board Six-Board

CAUTION: Before installing the Gateway board, verify the jumper JP7 (located near the top center of the board) is set to the “NOR-

MAL” position (not the “TEST” position). Operating the Gateway with the jumper in “TEST” position may cause board damage.

The Gateway Board communicates with the MRLDS via the Modbus network, which is connected to the Gate- way’s “Receiver Bus” network terminal. The Gateway communicates with the E2 via the RS485 I/O Network.

4.3.4Powering the Gateway

Board

Input Voltage	24VAC, Class 2, Center-Tapped
	50/60Hz
Power	5VA

Table 4-4- Gateway Power Requirements

The Gateway board requires 24VAC power from a Class 2 center-tappedtransformer. CPC supplies several sizes of center-tapped transformers for powering multiple 16AIs, 8ROs, and other RS485 peripheral boards.

Figure 4-8shows how to connect the 56VA and 80VA transformers to the Gateway power connector.

	Three-Board	Six-Board
P/N	640-0056	640-0080
Power Rating	56 VA	80 VA

Table 4-5- Power Ratings for CPC Transformers

Figure 4-8- Pinout for the 56VA (640-0056) and 80VA (640-

0080) Transformers

CAUTION: The MRLDS unit requires a sepa- rate Class 2, 24VAC, 10VA power supply.

4.3.5Connecting the Gateway Board to the Einstein or REFLECS Network

Each E2, Einstein, or REFLECS site controller that will communicate with one or more MRLDS units must have a Gateway Board installed on its RS485 I/O Net- work. For Einstein controllers, this means the Gateway will be installed on the RS485 I/O Network; for RMCC, BEC, BCU, and other REFLECS products, the Gateway will be installed on the COM A or COM D network.

4.3.6Wire Connections

Using shielded three-conductor network cable (Belden #8641 or equivalent), connect the RS485 I/O Network wire to the three-terminal connector on the Gateway board as shown in Figure 4-9. For further information about how RS485 networks are configured, refer to your site

8 • MRLDS I&O Manual 026-1307 Rev 1 11-30-07