Emerson MultiFlex RTU, Installation And Operation Manual

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Differences Between the MultiFlex RTU and ARTC Overview of the MultiFlex RTU • 1
1 Overview of the
MultiFlex RTU
The MultiFlex Rooftop Unit Board (RTU) (
P/N
810-3062
) is a “smart” combination input/output
board designed to control package rooftop
HVAC units. The MultiFlex RTU is capable of
controlling heat and cool stages, fans,
humidification and dehumidification devices,
economizers using on-board I/O and control
algorithms, as well as monitor and interact with
other building control systems and peripherals
(such as smoke alarms and CO2 sensors).
1.1. Differences Between the
MultiFlex RTU and ARTC
The MultiFlex RTU is a hardware replacement
for Emerson’s ARTC rooftop unit control
boards, which are now discontinued. The RTU
firmware is in every way identical to the ARTCs,
and is compatible with both Einstein BX and the
REFLECS BCU controllers. The only difference
between the RTU and ARTC is the RTU uses the
MultiFlex hardware platform, which is smaller
and more robust.
1.2. The RTU’s I/O Points
The compact size of the RTU allows technicians
to easily field-mount the RTU in a rooftop unit
or enclosure close to it, allowing for easy local
connection of sensors and transducers. The
board has eight analog inputs, pre-configured for
quick connection to space temperature sensors,
supply and return air temperature sensors, and
fan and compressor proofs. Its eight relay
outputs, rated 2.0 amps max, are used for
activating and deactivating fans, heat and cool
stages, economizers, and other systems or
devices.
1.3. Independent System
Control
The RTU can control a rooftop unit
independently without the need of a central
controller (such as Emerson’s Einstein BX
Refrigeration Controller). However, the RTU is
designed to interface with an Einstein BX or
BCU to allow it to work with other RTUs
together to control large zones. Networking RTU
to a central controller also allows you to view
status on Einstein & UltraSite32 status screens,
report alarms, and control dehumidification.
The RTU’s configuration can be programmed
either with ans Emerson Hand-Held Terminal
(HHT) or through the Einstein front panel.
LEGEND
1 INPUT POWER
(24VAC)
9 RS485 I/O TERMINATION
JUMPERS
2 RS485 I/O NETWORK 10 HAND-HELD TERMINAL
JACK
3 RTU INPUTS 1-8 11 RELAY OUTPUT
CONNECTORS
4 RTU INPUTS 9-16 (NOT
ACTIVE FOR RTU)
12 RELAY OUTPUT FUSES
(2A rated, 250V slow-blow)
5 NETWORK ID DIP
SWITCHES (S3, S4)
13 RELAY STATUS LEDs
6 INPUT TYPE DIP
SWITCHES (S1, S2)
14 OUTPUT FAIL-SAFE
SWITCHES
7 BOARD STATUS LEDs
(Code A, Code B, General
Status)
15 ANALOG OUTPUTS (#1
and #2 active for RTU, #3
and #4 inactive)
8 DC POWER OUTPUTS
(3 at +5VDC, 1 at
+12VDC)
16 NETWORK STATUS LEDs
Table 1-1 - MultiFlex RTU