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Bradford White Corp.
12.8 Control Snapshot
The software allows you to take a “snapshot” of
the current state of the controller, including setup
information and operating information. This
information can be helpful during troubleshooting.
How to get there –
Home Page <Setup button> Setup Screen <Control
Snapshot button> Control Snapshot Screen
Figure 138 shows the Control Snapshot screen.
fig. 138 - Control Snapshot list Screen
Select one of the controllers listed on the right side
of the screen. Press one of the buttons below the
right column to see the snapshot. See Fig. 139.
fig. 139 - typical Control Snapshot
The Show Status button captures the current status
of the I/O of the control only. Show Configuration
captures the current parameter settings and the
control setup. You can save the snapshot, give it a
name, or send a copy to the USB port.
12.9 operating Sequence
Initiation
Each controller enters the Initiation sequence after
one of these conditions:
•
Initial power up
•
Voltage fluctuations vary +10% or -15%
•
Frequency fluctuations vary ±10%
•
The demand, limit control input, or TT signals
are interrupted during the prepurge period.
•
After the Reset button is pressed.
•
After a Fault is cleared using the displays.
The Initiation sequence also delays the boiler
demand from being energized and re-energized from
an intermittent AC line input or control input. If
an AC problem exists for more than 240 seconds, a
lockout will occur.
Start-Up Checks in a lead/lag System
For an explanation of Lead/Lag operation, see the
first part of Section 9. In this section, we will focus
on the aspects of Lead/Lag that might be helpful in
troubleshooting.
When a Lead/Lag system is first powered up, the
controller acting as the Lead/Lag Master goes
through a “synchronization” process. During
synchronization, the controller establishes
communications with each of the Slave controllers
via the Modbus link. The Slave controllers
download some setup parameters and operating
history information. (On a system with several
boilers, this phase can take several minutes.) If the
Master cannot establish communications with one of
the Slaves, it triggers a Hold or Lockout.
The Master also checks the status of each of the flap
valves. If the Master cannot determine whether a
flap valve is open or closed, or if it cannot locate the
correct number of flap valves, it triggers a lockout or
hold.
If the system passes the checks described above,
each of the individual controller and burner
combinations is free to operate in the normal
way. The self-check and firing sequence for each
individual controller and burner combination is
described in the following section.
Summary of Contents for BNTH1000
Page 2: ...Bradford White Corp...
Page 12: ...Page 8 Bradford White Corp Fig 6 Dimensions BNT 1700...
Page 38: ...Page 34 Bradford White Corp Fig 21 Ladder Diagram...
Page 39: ...Page 35 Brute Elite Boilers and Water Heaters Fig 22 Wiring Diagram...
Page 40: ...Page 36 Bradford White Corp...
Page 52: ...Page 48 Bradford White Corp Fig 51 Connection Terminals...
Page 130: ...Page 126 Bradford White Corp Fig 141 Rear Panel BNT1000 Fig 142 Rear Panel BNT1700...
Page 131: ...Page 127 Brute Elite Boilers and Water Heaters Fig 143 Machine Frame BNT1700...
Page 132: ...Page 128 Bradford White Corp Fig 144 Front Panels and Covers BNT1000 and BNT1700...
Page 133: ...Page 129 Brute Elite Boilers and Water Heaters Fig 145 Burners and Combustion Chamber BNT1000...
Page 134: ...Page 130 Bradford White Corp Fig 146 Burners and Combustion Chamber BNT1700...
Page 136: ...Page 132 Bradford White Corp Fig 149 Burner Detail BNT1700...
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Page 140: ...Page 136 Bradford White Corp This page intentionally left blank...