AERCO KC1000 Boiler equipped with C-More 2002 - Manual (Page 18)

INSTALLATION
2-8
(Direct Drive Mode) of the Boiler. These formats
are:
4 to 20 mA/1 to 5 Vdc
0 to 20 mA/0 to 5 Vdc
PWM – (Pulse Width Modulated signal. See
paragraph 2.7.4)
Network – (RS485 Modbus. See para. 2.7.7)
While it is possible to control one or more boilers
using one of the above modes of operation, it
may not be the method best suited for the
application. Prior to selecting one of the above
modes of operation, it is recommended that you
consult with your local AERCO representative or
the factory for the mode of operation that will
work best with your application. For more
information on wiring the 4 to 20 mA / 1to 5VDC
or the 0 to 20 mA / 0 to 5 VDC, see paragraph
2.7.3.
2.6.5 COMBINATION MODE
NOTE
Only BMS Model 168 can be utilized for
the Combination Mode, not the BMS II
(Model 5R5-384).
With a Combination Mode unit, field wiring is
between the unit’s I/O Box, the CCP
(Combination Control Panel), and the BMS
Model 168 (Boiler Management System). The
wiring must be done using a shielded twisted
pair of 22 AWG wire. Polarity must be
maintained between the unit, the CCP, and the
BMS. For further instructions and wiring
diagrams, refer to the GF-108 Boiler
Management System Operations Guide and the
CCP-1 data sheet.
2.7 I/O BOX CONNECTIONS
The types of input and output/signals and
devices to be connected to the I/O Box terminals
shown in Figure 2.11 are described in the
following paragraphs.
CAUTION!
DO NOT make any connections to the I/O
Box terminals labeled “NOT USED”.
Attempting to do so may cause equipment
damage.
2.7.1 OUTDOOR SENSOR IN
An outdoor air temperature sensor (AERCO Part
No. 122790) will be required mainly for the
Indoor/Outdoor Reset mode of operation. It can
also be used with another mode if it is desired to
use the outdoor sensor enable/disable feature.
This feature allows the boiler to be enabled or
disabled based on the outdoor air temperature.
The factory default for the outdoor sensor is
DISABLED. To enable the sensor and or choose
an enable/disable outdoor temperature, see the
Configuration menu in Section 3 and Appendix
A.
The outdoor sensor may be wired up to 200 feet
from the boiler and is connected to the
OUTDOOR SENSOR IN and the SENSOR
COMMON terminals in the I/O box (see Figs.
2.10 and 2.11). Wire the sensor using a twisted
shielded pair cable of 18-22 AWG wire. There is
no polarity when terminating the wires. The
shield is to be connected only to the terminals
labeled SHEILD in the I/O Box. The sensor end
of the shield must be left free and ungrounded.
When mounting the sensor, it must be located
on the North side of the building where an
average outside air temperature is expected.
The sensor must be shielded form direct sunlight
as well as impingement by the elements. If a
shield is used, it must allow for free air
circulation.
2.7.2 AUX SENSOR IN
The AUX SENSOR IN terminals can be used to
add an additional temperature sensor for
monitoring purposes. This input is always
enabled and is a view only input that can be
seen in the operating menu. The sensor must be
wired to the AUX SENSOR IN and SENSOR
COMMON and must be similar to AERCO
BALCO wire sensor P/N 12449. A resistance
chart for this sensor can be found in Appendix
C.
2.7.3 ANALOG IN
The ANALOG IN + and – terminals are used
when an external signal is used to drive the
firing rate (Direct Drive Mode) or change the
setpoint (Remote Setpoint Mode) of the Boiler.
Either a 4 to 20 mA / 1 to 5 VDC or a 0 to 20
mA / 0 to 5 VDC signal may be used to vary the
setpoint or firing rate. The factory default setting
is 4 to 20 mA / 1 to 5 VDC, however this may be
changed to 0 to 20 mA / 0 to 5 VDC using the
Configuration Menu described in Section 3. If