CEMP-E
TI 810-11
30 November 1998
array shown.
e. Figure 4-6d shows the general arrangement of the back panel, which will have two vertical wiring
ducts and four horizontal wiring ducts, with covers as shown. The mounting rail shown at the top of the
panel will accommodate up to 15 relay bases, which will accept the wiring for plug-in relays. The relays
will be placed from right to left in the numerical order of their unique identifiers. Below the relay
mounting rail will be a horizontal wiring duct, and below this duct there will be three mounting rails and
wiring ducts that will accommodate the terminal blocks to accept the control system wiring. There will be
a mounting rail for function modules, time clock, and power supply located below the terminal block
mounting rails and wiring ducts; loop drivers may also be mounted on this rail. A duplex receptacle,
intended for maintenance use, will be mounted on the right side of the cabinet. The power conditioner
and system fuses will be mounted on the left side of the cabinet. The system's dc power supply will be
located to the left of the clock. The ac wiring will enter the wiring duct on the lower left of the panel and
will be distributed vertically. The dc wiring will enter the wiring duct on the right and will also be
distributed vertically.
f. The relative location assignments for three rows of numbered terminal block locations are shown
in figure 4-6e. Only the terminal blocks needed for the specific control system loops will be included in
the panel. Locations 1 through 70 in row 1 are dedicated to controller loop wiring in groups of 10.
g. Figure 4-6f shows the standard wiring for a typical controller and for a controller used as an
economizer controller. The left side of the figure shows that terminal 1 is always a shield terminal, and
that terminals 2 and 3 are always for the transmitter connection. These terminals are designated as PV.
Terminal 2 is connected to a dc-power terminal block and is jumpered to terminal 4 to supply power to
the CPA; terminals 4 and 5 make the CPA available to EMCS. The signal returns of PV and CPA are
connected to a dc-power terminal. Terminals 6 and 7 are wired to PVR and allow the 4-20 ma PVR
signal to be connected to EMCS. Terminals 8 and 9 are wired to OUT. Removal of the jumper
connecting terminals 8 and 9 will allow the controller to interface with an electric actuator rather than an
IP. The controller, TC, powers its output loop. Terminal 10 is an additional shield terminal. The right
side of the figure shows that when the controller is used as an economizer controller, terminals 2 and 3
are connected to the return air temperature transmitter, and terminals 6 and 7 are connected to the
outside air temperature transmitter. Terminals 8 and 9 contain the jumper for EMCS interface to the
economizer logic.
h. Figure 4-6g shows the standard wiring for the HVAC system's supply fan and return fan starters.
The "ENABLE-OFF" switch is connected to the supply fan only. If there are no smoke dampers, a
jumper will be installed between terminals 185 and 186. 100-percent outside air systems with high-
pressure fans will have end switches on the outside air damper to insure that the damper is open before
the fan starts. 100-percent outside air units with electric actuators will have end switches on the outside
air damper because of the inherently slower speed of the electric actuators in opening the damper.
Under normal conditions, local control switches for the supply fan, return fan, and exhaust fan starters
will be in the "AUTO" position. When the "ENABLE-OFF" switch is indexed to the "OFF" position, the
return and exhaust fans will stop when the supply fan stops, through interlocked relay contacts in the
"AUTO" position of the local starter control switch.
i. Figure 4-6h shows the wiring of exhaust fans when interlocked to other fans and also shows the
wiring of pumps. The left side of the figure shows the exhaust fan wiring. This wiring is similar to the
return fan wiring, except that a jumper is shown installed between terminals 205 and 206 because
exhaust fans do not normally require the circuitry to prove that the exhaust dampers are open before the
fan starts. If high-pressure fans are used for exhaust fans, the exhaust dampers should have end
4-6
Previous Page
