Preferred JC-15D2 Installation instructions

SDI-JC-15D2 rev 11-17-21 page 1 of 10
Preferred Utilities Mfg Corp
Preferred Instruments div.
31-35 South Street, Danbury CT 06810
203-743-6741 www.preferred-mfg.com
JC-15D2
Flue Gas Temperature Monitor
Installation & Operation Instructions
Why should Flue Gas Temperature be Monitored ?
 Every 40 F increase in Flue Temperature results in an approximate 1% decrease in Boiler/Furnace Efficiency.
 High Flue Temperature can indicate a need to clean soot or scale build-up on the tubes.
 High Flue Temperature can indicate fallen refractory, baffle damage, short circuiting, or overfiring.
 High Flue Temperature can indicate insufficient feedwater
 Hartford Steam records show that Boiler Overheating is the primary reason for Boiler Damage.
JC-15D2 Features
 Precise digital Temperature Indication
 Type J or K thermocouple Input
 Field selectable: T/C type, F/C, Alarm Setpoints, Alarm Delays, ….
 Manual Reset High-High “shutdown” Alarm
 Color Touchscreen
 50 pt Alarm/Event History, Time/Date Stamped
 Only 4 7/8” deep, fits in most existing burner control cabinets
 Plug-in field wiring terminals
 Ethernet, RS485, and 4-20mA outputs for Bldg Automation Systems
 USB port for configuration read/write with free JC_Edit Windows software
Description
The JC-15D2 Flue Gas Temperature Monitor is a digital Indicator and Alarm. Flue gas
temperature is displayed on a backlit color touchscreen LCD display. An intuitive
bargraph display and alarm messages provide clear stack temperature status. Bargraph
Scaling, Alarm Setpoints, and Time Delays are all field selectable. All adjustments can
be made directly from the faceplate of the instrument by navigating through user friendly menus. JC_Edit PC software can also be
used to configure the JC-15D2 via the USB port and to import the Alarm/Event History into JC_Edit.
Any J or K thermocouple can be used with the JC-15D2 to sense the temperature. The 20” 104087D and the 12” 104087E are
constructed with an Inconel sheath for corrosion protection, ½" male NPT process connection, cast iron head with terminal block,
and ½" female NPT electrical connection.
Table of Contents:
SAFETY .............................................................................. 2
Alarm Sequence ................................................................. 2
Operation ............................................................................ 3
Installation ........................................................................... 4
JC-15D2 Indicator Mounting: ......................................... 4
Temperature Sensor Mounting: ..................................... 4
Wiring: ............................................................................ 4
Menu Map ........................................................................... 5
Screen Settings.............................................................. 6
Alarm Setpoint Parameters ............................................ 6
Configure/Setup Parameters ......................................... 6
Troubleshooting ................................................................. 7
Modbus Communications ................................................... 7
Specifications ..................................................................... 8
Ordering Information: ......................................................... 8
Full Size Template ............................................................. 9

SDI-JC-15D2 rev 11-17-21 page 2 of 10
SAFETY
DANGER
Electric Shock Hazard
Multiple power sources may be present.
Disconnect all electric power sources, local and remote, before servicing
WARNING
This product is intended for use in Commercial and Industrial installations,
it is NOT intended for Residential use.
This product is intended to be used by Trained Operators.
Installation, start-up, and troubleshooting is intended to be done by
Experienced Technicians familiar with Industrial Safety Codes
and all Safety Codes specific to burners and boilers.
This product is NOT a Primary Safety Interlock rated device.
The Shutdown Relay Output should only be used as an
additional auxiliary Operating limit and should not replace or bypass
any Primary Safety Interlock devices required by Safety Codes.
Incorrect wiring connections to burner/boiler Flame Safeguard controls
can cause Equipment Damage, Injury, or Death
Alarm Sequence
The Bargraph and Numeric display continuously indicate the flue gas temperature (FGT). The “Warning” and “Shutdown” alarm
setpoints are indicated on the bargraph with tic marks. If the FGT exceeds the Warning Setpoint for more than 30 seconds
(adjustable), the bargraph blinks, the WARNING message appears, the Common Alarm Relay energizes, and the current
temperature is logged with a time/date stamp. Pressing the ALARM SILENCE button de-energizes the Common Alarm Relay.
If the FGT continues to increase and exceeds the Shutdown setpoint for more than 15 seconds (adjustable), the bargraph blinks,
the SHUTDOWN message appears, the Shutdown relay de-energizes and latches into “Manual Reset” mode, the Common
Alarm Relay re-energizes, and the current temperature is logged with a time/date stamp. Pressing the ALARM SILENCE button
de-energizes the Common Alarm Relay.
If the JC-15D2 Shutdown relay is wired into the burner Start Limits, the burner shuts down. The Shutdown Relay remains
de-energized and the SHUTDOWN message remains on the display. After the temperature has fallen below the “shutdown”
setpoint, the Operator can press the RESET pushbutton to energize the Shutdown relay.
The Common Alarm Relay can be used to activate an external bell or horn. If the JC-15D2 is not in SHUTDOWN, the Common
Alarm Relay de-energizes automatically when the temperature drops below the Warning Alarm setpoint. Alternately, pressing the
JC-15D2 Alarm Silence pushbutton, or energizing the 120 Vac Alarm Silence input, or the 24 Vdc Alarm Silence input, or
sending a Modbus command will de-energize the Common Alarm Relay in order to silence an audible alarm.

SDI-JC-15D2 rev 11-17-21 page 3 of 10
Operation
Home Screen
The current Flue Gas Temperature (FGT) is displayed at the top. The Bargraph height varies in
proportion to the FGT. The lines on the right side of the bargraph are the Warning and
Shutdown Alarm setpoints.
The lower left button on all screens indicates one of these three words:
Silence or Alarms or History
When a new Alarm occurs, Silence and the bargraph blink, and the Common Alarm Relay
Output energizes. Touch Silence to stop the blinking and to de-energize the Alarm Relay.
Alarms is displayed after silencing, IF an Alarm is still active.
History is displayed when there are no active Alarms.
A Shutdown Alarm latches and requires a manual reset after the temperature has dropped
below the Shutdown setpoint. The RESET button is only displayed when a reset is required.
Alarms Screen
From any other screen, touch the Alarms button to display the Active Alarms Screen.
If there are no active Alarms, Alarms will not be displayed on the Main and Menu screens.
All active Alarms are displayed on this screen: Warning Alarm, Shutdown Alarm,
Thermocouple Open, etc….
The Alarm temperature and time/date shown occurred when the Alarm time delay expired and
the alarm triggered.
When the Alarms screen is displayed, History and Back are displayed.
Touch History to display the History screen.
Touch Home return to the Home screen.
History Screen
Touch History to display the History screen.
The History screen displays the Time/Date of the most recent 50 Alarms and Events.
Events include: peak temperatures, when an Alarm Clears, a Shutdown Reset, JC-15D2
power-up, etc..
Touch the Up or Down arrow to advance to the next page of History.
Touch Date to enter a time/date and then to jump to the nearest History records.
The Hide Events and Show Events removes or displays Events.
The History memory is retained when powered down. The History can be extracted via the
USB port using the free JC_Edit Windows App.
Menu Screens
To set clock, Alarm Setpoints, and other initial Setup…..See pages 5 and 6
HomeHistory
High Flue Temp. SHUTDOWN
432 F RESET REQ’D 16:30:02
8/17
High Flue Temp. Warning
382 F WARNING 16:23:59
8/17
Active Alarms
0
125
250
375
500
FLUE GAS F
433
History
Alarms
R
E
S
E
T
Silence Menu
High Flue Temp. Shutdown
197 F RESET 17:21:12
8/17
High Flue Temp. Warning
375 F CLEAR 16:48:01
8/17
Peak Temp.
467F 16:33:07
8/17
High Flue Temp. Shutdown
432 F SHUTDOWN 16:30:02
8/17
High Flue Temp. Warning
382 F WARNING 16:23:59
8/17
History
Alarms
Silence Home
Date
Hide
Events
Show
Events

SDI-JC-15D2 rev 11-17-21 page 4 of 10
Installation
JC-15D2 Indicator Mounting:
The JC-15D2 Indicator is designed for flush mounting in an
enclosure located in an indoor NEMA 12 environment.
The JC-15D2 should not be subjected to excessive vibration.
Continuous operation is guaranteed over the 32-131 F (0-55C)
ambient operating range.
See Full Size Cutout Template on the last page
Temperature Sensor Mounting:
The 20” 104087D and the 12” 104087E type J thermocouple temperature
sensors are designed for mounting in a NEMA 4 environment.
The thermocouple should not be subjected to excessive vibration.
Locate the temperature sensor where the tip of the probe will sense a representative flue gas temperature.
Typically, the tip should be in the middle 1/3 of the flue gas duct. Shielded T/C extension wire is recommended.
Wiring:
Warning
Disconnect all sources of power before installing or servicing this equipment. Multiple Disconnects may be required.
Burner interface wiring must be performed by an experienced burner service technician.
All wiring must comply with all local and national electrical codes. Tighten all terminals to 4.4 in-lb. Wire must be stranded copper,
12-24 ga., 150V / 75 C insulation minimum. AC and DC wiring must be separated to prevent electrical noise coupling. Do not run
AC and DC wires in the same conduits. Use shielded cables where shown, connect shields only where shown, insulate all other
shields to prevent accidental grounding. Ignition transformer and motor VFD wiring are particularly noisy and should be kept away
from the thermocouple extension wire, and also all other AC and DC wiring.
 The wiring from the thermocouple to the JC-15D2 must be thermocouple extension wire. Do not use copper wire for any part
of this wiring. Use the same wire type as the thermocouple: type J wire for a type J thermocouple.
 The Red wire is the '-' for all thermocouple types. Connect the Red wire to the red or '-' screw in the thermocouple head.
Connect the Red wire to JC-15D2 terminal 33.
 Avoid splicing the thermocouple extension wire. Each splice is a potential source of temperature error.
 If shielded thermocouple wire is used, insulate the shield wire inside the thermocouple head to prevent shorting to ground.
 NO wiring on terminals 36 or 38. This can cause incorrect temperature readings, or a false “Open T/C” Alarm.
 If the 4-20 mA output will not be used, jumper terminal 39 to 40 to prevent the OUTPUT FAILURE error message.
 Relay contacts are shown with power removed from the JC-15D2. In normal operation Relay 2 is energized.
Relay 2 de-energizes to shutdown the burner.
 All DC wiring is isolated from Ground. All DC wiring '-' terminals are connected together internally.
 RS485 is electrically Isolated from all other DC and AC wiring.
 Terminals 1-9 are Line Voltage AC. Terminals 31-50 are low voltage DC.
 An external Line Voltage supply switch or circuit breaker, marked as the disconnect for this instrument, suitably located and
easily reached, and complying with IEC 60947-1 and -3 must be provided.
Fuse: 0.5 amp Slo-Blo, 250 V, 5x20mm (Littlefuse 0239.500HXP, Belfuse 5TT 500-R, Preferred Utilities 16740-0.5S)
Caution: To reduce the risk of fire, only replace fuse with the same type.
Panel Cutout
3.61 x 7.65
3.88
8.00
Touch
Screen
8.74
Plug-in Terminals
1.00
4.88
Plug-in Terminals

SDI-JC-15D2 rev 11-17-21 page 5 of 10
Wiring (continued):
Menu Map
JC-15D2 Indicator
40
39
-
+
Temperature
4-20 mA
L1
N
N
H
120 Vac
26 VA
50/60 Hz
45
47
49
RS485 +
RS485 -
Common
Optional Remote
Alarm Silence
Pushbutton
3
2
1
Common Alarm Relay
Relay 1
External Alarm
Circuit
(Relay Energizes when in Alarm)
Shutdown Relay6
5
4
Burner Limits
Circuit
Relay 2
(Relay De-Energizes to
Shutdown Burner)
7
34
33
41
red
Type J or Type K
Thermocouple white = type J
yellow = type K
Shielded Thermocouple Extension Wire
Do not run in conduits with AC wiring.
+
-
Shield
(Line Voltage AC Wiring)
red
G
G
Ethernet
44
43
+
-
(24 Vdc Wiring)
Main Menu
Utilities
Password
Alarms
Configure / Setup
Thermocouple
T/C Type
F/C
Filter Seconds
Temperature Adjust
Bargraph
Top of Bargraph
Bottom of Bargraph
4-20 Output
20 mA = xxx Deg
4 mA = xxx Deg
Configure / Setup
Thermocouple
Bargraph
4-20 Output
RS485
Ethernet
Utilities
Set Clock
Calibrate Screen
Clean Screen
Screen Settings
Firmware Version
Startup History
Alarms
Warning Setpoint
Warning Delay
Shutdown Setpoint
Shutdown Delay
Password
Enter
Change
Logout
Screen Settings
Brightness
Touch Tone
Alarm Tone
RS485
Baud
Parity
Stop Bits
Address
Ethernet
Address
Mask
Gateway

SDI-JC-15D2 rev 11-17-21 page 6 of 10
Screen Settings
Parameter
Default
Max.
Min.
Goto:
Menu > Utilities > Screen
Settings
1
Disable
Enable
Disable
Touch Buzzer Enable
Activates faceplate Tone when a screen item is touched
2
Disable
Enable
Disable
Alarm Buzzer Enable
Activates faceplate Tone when a
n Alarm is triggered.
Alarm Setpoint Parameters
Parameter
Default
Max.
Min.
Goto: Menu > Alarms
3
400
2000
100
W
arning Setpoint (degrees)
This Setpoint is used for the Warning Alarm logic.
4
30
1200
1
W
arning Delay (seconds)
The Common Alarm relay energizes when the Temperature has been above the
Alarm Setpoint for more than 'Warning Delay' seconds.
Once the Warning Alarm has been triggered, the temperature must drop 5 degrees
below the Setpoint before the Warning Alarm de
-
ac
tivates.
5 490 2000 200
S
hutdown Setpoint (degrees)
This Setpoint is used for the Shutdown Alarm logic.
6 15 300 1
S
hutdown Delay (seconds)
The Shutdown relay de-energizes when the Temperature has been above the
Shutdown Setpoint for more than 'Shutdown Delay' seconds.
The temperature must drop 5 degrees below the Shutdown Setpoint and the
Operator must press the RESET button in order to re
-
energize the Shutdown relay.
Configure/Setup Parameters
Thermocouple
Parameter
Default
Max.
Min.
Goto: Menu > Configure / Setup > Thermocouple
7
J
J
K
T/C Type
Type J thermocouple: -40 F to 1200 F (-40 C to 649 C )
Type K thermocouple:
-
40 F to 1700 F (
-
40 C to 927 C )
8 F C F UNITS Fahrenheit or Centigrade.
9
2.0
30.0
0.5
F
ilter Seconds
Dampens (smooths) rapid temperature display variations.
Larger values = more damping. Smaller values = less damping.
10
0
+10
-
10
T
emperature Adjust
(degrees)
The displayed value is offset from the measured value by this amount for all
temperatures. Used to calibrate out minor temperature differences due to sensor
errors. The units are F or C, as selected above.
Bargraph Range
Parameter
Default
Max.
Min.
Goto: Menu > Configure / Setup > Bargraph
11 500 2000 0 Top of Bargraph
This is the temperature value at the top of the bargraph.
The units are F or C, as selected above.
12 100 2000 0 Bottom of Bargraph
This is the temperature value at the bottom of the bargraph.
The units are F or C, as selected above.
4-20 mA Output
Parameter
Default
Max.
Min.
Goto: Menu > Configure / Setup > 4
-
20 Output
13
1000
2000
100
20
m
A =
This is the temperature value for
20 mA output.
14
0
1900
0
4
m
A =
This is the temperature value for 4 mA output.

SDI-JC-15D2 rev 11-17-21 page 7 of 10
Troubleshooting
The displayed temperature is not what you expected:
 Verify that the Red wire is connected to the Red (‘-‘) terminal of the thermocouple and to terminal 33 of the JC-15D2.
 Verify that there is NO wiring on terminals 36 or 38. This can cause incorrect readings, or a false “Open T/C” Alarm.
 Verify that the INPUT TYPE and DISPLAY UNITS are set correctly in the DISPLAY MENU.
 Remove the thermocouple wire from JC-15D2 terminals 33 & 34. Jumper terminal 33 to terminal 34 with copper wire. The
JC-15D2 should display the ambient temperature near the JC-15D2 terminal blocks.
 If the ambient temperature is displayed with the jumper installed, then the problem is in the interconnecting wiring, or the
thermocouple is the wrong type.
 Verify that the wiring from the thermocouple to the JC-15D2 is the correct type of thermocouple wire (and not copper wire).
The standard color code is red and white for type J, and red and yellow for type K.
 Move the tip of the thermocouple within the duct to determine if the temperature changes.
 Check for loose splices in the field wiring. Check for shields touching ground.
Modbus Communications
RS485 Baud: 4800, 9600, 19200, 38400, 57600
RS485 Parity: Odd, Even, None
Ethernet: 10/100 Mb/s
Protocol: RTU
Address: 1-247
Register Formats: 16 bit Signed Integer and 32 bit Floating Point
Modbus Commands: 01 Read Coils, 03 Read Registers, 05 Write Single Coil, 06 Write Single Register,
16 Write Multiple Registers (2 registers max)
Max Poll Size: 120 coils or registers (except Code 16)
Coil 0 = 1 = Description
98 RW Silence Alarm Silence
99 RO Energized Common Alarm Relay
100 RO Warning Warning Alarm
101 RO Shutdown Shutdown Alarm
Register F / I Description
40100 F RO Temperature
40106 F RO Shutdown Setpoint
F = Floating Point, I = Integer, RO = Read Only, RW = Read/Write

SDI-JC-15D2 rev 11-17-21 page 8 of 10
Specifications
Mechanical:
Enclosure: Nema 12 Faceplate, Indoor Locations
Bezel Size: 3 7/8 w x 8 h x 1 d
Rear Case Size: 3 1/2 w x 7 9/16 h x 4 7/8 d
Panel Cutout: 3.61 w x 7.65 h
Weight: 2 lbs
Ambient Temp.: 32-131 F (0-55 C)
Max. Altitude: 6560 feet (2000 meters)
Electrical:
Input Power: 120Vac +/-15%, 50/60 Hz, 26 VA
Output Power: 24 Vdc, 300mA max combined load
Terminals: 31,35,37,40,42
Inputs
Sensor: Type J or K thermocouple
(field selectable J/K and F/C deg.)
0.1 deg F resolution
0.5 F linearity
Upscale Break Protection
Remote Silence: (1) 120 Vac / 13 mA, Optically Isolated
(1) 24 Vdc Sinking, 0.7 mA
Outputs
Temperature: 4-20 mA, 650 ohm load
(field adjustable scaling)
Relay Outputs: (2) 120Vac,10 A SPDT
Communications: RS485 and Ethernet (see Modbus)
USB for JC_Edit Windows App
Ordering Information:
Part Number Description
JC-15D2 Flue Gas Temperature Monitor
104087D 20" Type J Thermocouple, ½" MNPT process connection
104087E 12" Type J Thermocouple, ½" MNPT process connection
92088-J-B20PP Shielded Type J thermocouple extension wire
SDA-B6 Alarm Bell, 6" dia, 85 db, 120 Vac
16740-0.5S 0.5 amp Slo-Blo, 250 V,5x20mm fuse
16740-3.15S 3.15 amp Slo-Blo, 250 V,5x20mm fuse
90437-KIT Panel Mounting Clip (2)
90434 Panel Mounting Gasket
92794 5 pt Terminal Block
92791 8 pt Terminal Block
92795 10 pt Terminal Block

SDI-JC-15D2 rev 11-17-21 page 9 of 10
Full Size Template
3.61
7.65
Edge of
Faceplate
(outside of panel)
Mounting
Bracket
(inside of panel)
JC-30D2
Panel Cutout

SDI-JC-15D2 rev 11-17-21 page 10 of 10
Preferred Utilities Mfg Corp
Preferred Instruments div.
31-35 South Street, Danbury CT 06810
203-743-6741 www.preferred-mfg.com