NTI Trinity Lx 150, Инструкция по установке и эксплуатации

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Lx Series Installation and Operation Instructions
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Trinity Lx
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Low Voltage Connections
The Trinity Lx low voltage junction box is located in the lower left corner of the boiler cabinet on Lx150-200
models and can be accessed by removing the front door of the boiler, followed by the removal of the low voltage
junction box cover. On Lx300-400 models, the low voltage junction box is located at the top of the boiler
cabinet on the left hand side and can be accessed by removing the top front cover of the boiler. On Lx500-800
models, the low voltage junction box is located at the back of the boiler cabinet and can be accessed by
removing the top back cover of the boiler. Each boiler is provided with one hole and two knockouts for routing
field wiring into the low voltage junction box. Low voltage field connections identified in Tables 12-2(a) and
12-2(b) are to be read in conjunction with Figure 12-2.
Table 12-2(a) Low Voltage Field Connections (Lx150-400)
Connection Location Description
COM
(24VAC)
1
24VAC Common – Neutral for the 24VAC power supply from the boiler. COM can be
used in conjunction with terminal R to provide a power source for a digital thermostat.
R
(24VAC)
2
24VAC Hot - Power supply for inputs LIM, CH1, and CH2 (LL).
3
LIM 4
External Limit – Input requiring 24VAC from terminal R to permit the burner to operate.
Comes factory equipped with a jumper to the R terminal. For installations requiring the
use of an additional safety switch, such as a LWCO, Flow Switch, or auxiliary temperature
limit, remove the factory installed jumper and install the normally open isolated contacts of
the additional limit in its place.
CH1 5
Local Central Heat Demand
– Input requiring 24VAC from terminal R to initiate a
“local” CH call. Switch is made using an isolated end switch (dry contact) via thermostat,
zone controller or other device. Typically used as the lone heat input or as the high
temperature input in dual CH temperature systems.
CH2 (LL) 6
Lead-Lag Central Heat Demand
–
Input requiring 24VAC from terminal R to initiate a
“lead-lag” CH call. Switch is made using an isolated end switch (dry contact) via
thermostat, zone controller or other device. Typically used as a lead-lag input for cascaded
boilers or as the low temperature input in dual CH temperature systems.
Sensor
DHW 7
DHW Tank Demand
–
Input requiring closure of terminals 7 and 10 to initiate a demand
for DHW. Switch made via isolated end switch (dry contact) from a thermostat (Aquastat)
located in an Indirect Fired Water Heater. Or optional Tank Sensor (P/N 84632), see
Appendix A. (
NOTICE : tank sensor cannot be used for cascade boiler arrangements).
OD
SENSOR
8
Outdoor Temperature Sensor
–
A wall mountable OD Sensor is included with each
boiler. When connected to terminals 8 and 10, the control will indicate the outdoor
temperature and adjust the boiler temperature set point during a Central Heat demand.
SYSTEM 9
System Water Temperature
–
An optional strap-on System Sensor is available from NTI
(P/N 84010). When connected to terminals 9 and 10, the control will indicate a “CH” or
“Lead-Lag” temperature. The control can be set to use the System Sensor as the
Modulation Sensor for a CH1 or Lead Lag demand; see Appendix A.
SENSOR
COM
10
System Common
–
Common port for field inputs DHW, OD Sensor, System Sensor and
Communication terminals.
4 -20mA
11 External Modulation Control – Using a 4-20mA signal, an external control can be used
to directly modulate the burner firing rate or adjust the active set point. This can be useful
for applications using external staging controls or Building Automation Systems.
12
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LL DATA+ 13 Lead-Lag
– Connects internally to the controller’s MB2, Modbus communication port.
Terminals 13, 14 and 10 (common) can be "daisy-chained" to multiple boilers (up to 8 in
total) for the purpose of staging.
LL DATA– 14
BMS D+ 15 Building Management System (BMS) – Connects internally to the display’s COM2,
Modbus communication port. Terminals 15, 16 and 10 (common) can be connected to a
Gateway for communication to a BMS or other device.
BMS D– 16
ALARM
17
Normally Open Alarm Contacts – Contacts close during a lockout or other alarm
condition. May be connected to a BMS, maximum capacity of 0.63Amps at 24VAC.
18