Johnson Controls VMA1930, Руководство по установке, Страница: 7 / 20

SA Bus port
The Sensor (SA Bus) port on the bottom of the
controller is an RJ-12, 6-position modular jack that
provides a connection for the Mobile Access Portal
(MAP) Gateway, the Bluetooth Commissioning
Converter (BTCVT), the VAV Balancing Tool, specified
network sensors, or other SA Bus devices with RJ-12
plugs. A DIS1710 Local Controller Display can also be
connected to the SA Bus port.
Note:
• Do not use the modular SA Bus port and the
terminal block SA Bus simultaneously. Only
use one of these connections at a time.
• The MAP Gateway serves as a replacement
for the BTCVT, which is no longer available
for purchase, but continues to be supported.
The Sensor port is connected internally to the SA
bus terminal block. For more information about
Sensor port functions, requirements, and ratings,
see Table 5.
Figure 4: Pin number assignments for Sensor
(SA Bus) Port on VMA1930
Supply power terminal block
The 24 VAC supply power terminal block is a
gray, removable, 2-terminal plug that fits into a
board-mounted jack on the upper left of the VMA
controller.
Wire the 24 VAC supply power wires from the
transformer to the HOT and COM terminals on the
terminal plug as shown in the following figure. See
Table 5 for more information.
Figure 5: 24 VAC supply power terminal block
wiring
The supply power wire colors may be different on
transformers from other manufacturers. Refer to
the transformer manufacturer’s instructions and
the project installation drawings for wiring details.
Important:
Connect 24 VAC supply power to
the controller and all other network devices
so that transformer phasing is uniform across
the network devices. Powering network
devices with uniform 24 VAC supply power
phasing reduces noise, interference, and
ground loop problems. The controller does not
require an earth ground connection. However,
when grounding the secondary of the 24 VAC
transformer is required, only one connection to
ground should be made near the transformer.
See the following figure.
Figure 6: Transformer Grounding
VMA1930 VAV Controller Installation Guide 7