Rosemount 6888Xi, Reference Manual, Page: 94 / 114

Adding an AC Relay Board to the 6888Xi
1. Loosen the four screws securing the 6888Xi cover. The screws are captive and do not need
to be completely removed.
2. Swing the 6888Xi cover down to expose the inner components.
3. Slide the I/O Board part way out of the 6888Xi enclosure.
4. Make the following jumper and switch settings:
a. Set SW4, Position 4 "ON" and all other positions "OFF".
b. Move the jumpers for both JP1 and JP2 to pins 1 and 2.
5. The I/O Board must be relocated to the right-most slot inside the 6888Xi enclosure. If there
is enough service loop on the 6888Xi wiring, slide the I/O Board completely out of the enclo-
sure and re-install it in the right-most slot. Ensure the board is correctly aligned within the
slots. See Figure 5-8 for the correct location of the I/O Board.
6. If there is not sufficient wiring, tag and disconnect all wiring, and relocate the board. Then
reinstall the wiring.
Section 5: Maintenance and Service Reference Manual
January 2019 00809-0100-4892
86 Maintenance and Service
FIGURE 5-7. I/O & AC Relay Board Flame Safety Interlock Wiring
NOTE
An AC Relay Board can only be added to single channel 6888Xi, i.e. only one I/O Board controlling one O2
Probe. The Flame Status Interlock function requires a contact closure on the digital input of the I/O Board to
indicate a flame is present. When properly connected and configured, AC power will be applied to the trans-
mitter only when the flame is present.