MU-TLPA02 Honeywell

The RAM chip can be permanently damaged by incorrect insertion.

(4) Insert the RAM expansion integrated circuit (HN6264ALP) into the

socket IC12 on the Engineering Card, ensuring that pin 1 of the IC

is aligned correctly with pin 1 of the socket and that all pins are

properly inserted into the socket.

(5) Using small pliers or an electrical screwdriver gently remove the

Engineering Card shorting link LK1 and replace to short pins 1 and

2. See Figure 7.

(6) This step applies to the RS485/422 module only. For correct

operation, especially at high baud rates, RS485 and RS422

highways should be resistively terminated.

In RS422 host systems, a terminator resistance is only required at

the receiver device located in the host and at the receiver device

located in the System 57 node at the far end of the cable.

In RS485 host systems, a terminator resistance is required at the

transceiver device located in the host and at the transceiver device

located in the System 57 node at the far end of the cable.

For dual highway RS485 systems, both highways should be

terminated as described above.

By default the RS485/422 module transceivers are unterminated. If

a resistive termination is required, use small pliers or an electrical

screwdriver to gently remove the shorting links, LK2 (Channel 1) or

LK1 (Channel 2), on the RS485/422 Module from pins 1 and 2 and

replace to short pins 2 and 3. (See Figure 1 and Section 3.4.3).

(7) Insert the MODBUS Interface Module into the socket headers J1

and J2 on the Engineering Card, ensuring that pin 1 of the module

pin headers is correctly aligned with pin 1 of the Engineering Card

socket headers.

(8) Re-insert the Engineering Card into the rack, tighten the two front

panel screws and go to the Section 3.4.