NTI Trinity Lx 150, Инструкция по установке и эксплуатации

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Trinity Lx
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Installation and Operation Instructions Lx Series
58
Table 12-2(b) Low Voltage Field Connections (Lx500-800)
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.
R1/R2 (24VAC)
2
24VAC Hot - Power supply for inputs EXT. LIM, CH1, and CH2 (LL).
3
EXT. LIM 4
External Limit – Input requiring 24VAC from terminals R1/R2 to permit the burner to
operate. Comes factory equipped with a jumper to the R2 terminal. For installations
requiring the use of an additional safety switch, such as a LWCO or auxiliary temperature
limit, remove the factory installed jumper and install the normally open isolated contacts of
the field supplied additional limit in place of jumper.
GAS LO PR.
5
Gas Low Pressure Switch (Optional) – Comes factory equipped with a jumper. For
applications requiring a Low Gas Pressure Switch, remove jumper and connect normally
open isolated contacts of the Gas Low Pressure Switch. Switch must be installed external to
unit (24VAC circuit). For preapproved High Gas Pressure Switch, see Note 1 below.
6
AUX. PROOF
7
Auxiliary Proof
– Comes factory equipped with a jumper. For applications using Indoor
Combustion Air, remove jumper and replace with field supplied end switch incorporated
with motorized damper/louver control.
8
CH1 9
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) 10
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.
Sen
so
r
DHW 11
DHW Tank Demand
–
Input requiring closure of terminals 11 and 14 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 / SYS
SENSOR
12
Outdoor Temperature Sensor
–
A wall mountable OD Sensor is included with each
boiler. When connected to terminals 12 and 14, the control will indicate the outdoor
temperature and adjust the boiler temperature set point during a Central Heat demand.
System Water Temperature
–
An optional strap-on System Sensor is available from NTI
(P/N 84010). When connected to terminals 12 and 14, the control will indicate a “Lead-
Lag” temperature. By default, the System Sensor becomes the Modulation Sensor for a
Lead Lag demand.
NOTICE: only one sensor can be connected to terminal 12 (System OR Outdoor Sensor);
see instructions in Appendix A.
TOD 13
Time of Day (Night Time Setback) – Input requiring closure of terminals 13 and 14 to
initiate TOD setback setting. Switch is made using an isolated end switch (dry contact)
using a timer, BAS or other device. [TOD applicable to and available on Lx500-800 only]
SENSOR
COM
14 System Common
–
Common port for field inputs DHW, OD Sensor and System Sensor.
4 -20mA (– / +)
15
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.
16
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LL DATA+ 17
Lead-Lag
– Connects internally to the controller’s MB2, Modbus communication port.
Terminals 17, 18 and 14 (common) can be "daisy-chained" to multiple boilers (up to 8 in
total) for the purpose of staging.
LL DATA– 18
BMS D+ 19
Building Management System (BMS) – Connects internally to the display’s COM2,
Modbus communication port. Terminals 19, 20 and 14 (common) can be connected to a
Gateway for communication to a BMS or other device.
BMS D– 20
ALARM (A&B)
21
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.
22
Notes
1
For applications requiring a High Gas Pressure Switch, see supplemental instructions included with NTI High Gas
Pressure Switch Kit, P/N 84094. Note that this is the only High Gas Pressure Switch that has been tested with the unit
and preapproved for field installation within the boiler cabinet.