York MILLENNIUM Y22, Installation Manual

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102777-YIM-E-0206
Unitary Products Group 99
EEPROM (Double “E” Prom) - Is also non-volatile, but this
type of memory requires a special process to be written to.
This memory can be written to and changed by the micropro-
cessor. This is the type of memory that the control program is
stored in the Simplicity control.
ROM - Read Only Memory is non-volatile but can not be writ-
ten to. This memory is programmed only once before the con-
troller is assembled. ROM contains instructions specifically for
the internal microprocessor computer in the controller.
FIRMWARE - “Firmware” is software, program instructions or
applications, but stored in EPROM or ROM memory.
RAM - Random Access Memory is a volatile memory. It will be
erased when a power fail occurs. This memory is used as a
kind of “scratch pad” for the controller. Temporary instructions
and information such as an output controlling action like driving
the economizer dampers open is stored here. When a power
loss occurs or if the controller is sent a manual reset using a
control push button, this memory is cleared and initialized.
Other filtered inputs include temperature and humidity sen-
sors. You should be aware of this filtering effect because it
will appear the controller is not acting as fast as you may
think it should. In reality, it is acting and controlling on these
time-averaged and weighted values.
FAULT TOLERANCE - Fault Tolerance of the Simplicity con-
trol involves two issues: Hardware fault tolerance deals spe-
cifically with the electrical characteristics of the controller -
how much over voltage or power surge the controller can
withstand before damage occurs, and whether internal com-
parisons are verifying that the control is calculating and com-
municating properly. Software fault tolerance in this
technology consists of comparing results to previous values
and to reasonable values.
COMMUNICATIONS BUS
Networked communications may also be new to you. It
relates to connecting several Millennium rooftop units to a
network that can be monitored and controlled remotely from
network computer workstations. You will find this typically on
large installations where central control, monitoring, and
energy management issues become a critical factor in oper-
ating a large complex such as a manufacturing facility.
The Simplicity Control has the ability to be networked into a
larger system using the MODBUS communication protocol. A
communication protocol is simply a set of rules that deter-
mine how two systems communicate with each other over
some medium such as a pair of wires, phone line, radio
waves, etc. The transmission medium may also be called a
gateway, pathway, or bus. An “open” protocol such as MOD-
BUS is a publicly published set of rules that any equipment
manufacturer can use to network into another manufacturers
equipment.
OPTIONAL ModLINC TRANSLATOR
Overview
The ModLINC translator operates as a Modbus
®
Client pro-
viding an interface between a BACnet
®
control system and
devices that communicate using the Modbus
®
RTU protocol.
The ModLINC is preconfigured to provide an interface to
YORK UPG products equipped with an Intelli-Comfort or Sim-
plicity-Elite controller and allows monitoring and control by an
ISN ConneXsys or third-party BACnet
®
Building Automation
System (BAS).
The ModLINC communicates using the Modbus
®
RTU proto-
col on one port and BACnet
®
MS/TP, which is the protocol
used by ISN ConneXsys devices, on the other port. By pro-
viding different communication protocols on the two ports,
data can be retrieved from and provided to two different sys-
tems.
The ModLINC mounts inside the control panel of the UPG
unit and utilizes 24 VAC power from the unit's control trans-
former. One port is connected to the UPG controller. The
other port must be connected to the ISN ConneXsys/BAC-
net
®
network.
The ModLINC translator is preconfigured to obtain opera-
tional data points from the controller and expose them on an
ISN ConneXsys/BACnet
®
network. The data can be trans-
ferred to any network device, including an ISN ConneXsys
OWS.
"The ModLINC device is primary a control offered and config-
ured by York's ESG (Engineering Systems Group). The
device is designed to tie into and function with the ISN Con-
neXsys system. The device can be used with other BACnet
®
MS/TP systems, but a qualified controls contractor must be
involved. UPG cannot support the ModLINC device beyond
its hardware functionality and cannot guarantee functionality
with the ISN or other third party BAS device."
Please refer to the ModLINC Installation/Application manual
Part Number 126367-UIM-A-0305.
COMPONENT DESCRIPTION
This section describes the main components of Millennium
Simplicity control. These components consist primarily of
controllers, hardware to handle signal input and control out-
put and the Tstat interface terminals.
THE SIMPLICITY CONTROLLER
Simplicity is a proprietary, microprocessor-based controller for
use in HVAC applications. The controller provides monitoring
and control for either VAV or CAV for a total of 22 outputs.