5 Electrical connections
External EMS connection to terminal strip for stage firing control of
Installation & Service Manual
Figure 5-2_Stand-alone operation
burners
This unit is equipped with a factory installed terminal strip for connection of an energy management system (EMS) to the burner stages. The EMS terminal strip is located in the unit’s control panel. Ensure that all wiring used for connection to this terminal strip is properly sized per the recommendations in TABLE 5A. When connecting an EMS to this terminal strip to sequence on each stage of burner operation, the unit’s internal thermostat or electronic sequencer should be set as an additional high limit control. This will prevent problems between the set
1 | + | SYSTEM/TANK |
2 | + | SENSOR |
3+ B2 INTERMITTENT
4+ B1 LIMITS
5+ A2 CONTINUOUS
6+ A1 LIMITS
7 |
|
| + | 2 NO HIGH FIRE | |
|
| ||||
8 |
|
| + | 2 C | ENABLE |
|
| ||||
9 |
|
| + | 1 NO LOW FIRE | |
|
| ||||
10 |
|
| + | 1 C | ENABLE |
|
|
6
7
8
9
10
1
2
3
4
5
points of the EMS and the boiler’s internal controller.
Figure 5-3_Remote on/off boiler or water heater
Terminal strip connection options
Figure
Figure
| 1 | + | SYSTEM/TANK | ||
| 2 | + | SENSOR | ||
| 3 | + | B2 INTERMITTENT | ||
| 4 | + | B1 | LIMITS | |
| 5 | + | A2 | CONTINUOUS | |
Remote | 6 | + | A1 | LIMITS | |
7 | + | 2 NO HIGH FIRE | |||
on/off | |||||
8 | + | 2 C | ENABLE | ||
| |||||
| 9 | + | 1 NO LOW FIRE | ||
| 10 | + | 1 C | ENABLE |
6
7
8
9
10
1
2
3
4
5
Figure
Figure
set point temperatures are controlled by the EMS. The High Fire Offset on the electronic temperature control in the unit must be set to zero and the set point must be set to a value which will function as an upper limit for proper operation under this
Figure
| 1 | + | SYSTEM/TANK | |
| 2 | + | SENSOR | |
| 3 | + | B2 INTERMITTENT | |
| 4 | + | B1 | LIMITS |
| 5 | + | A2 | CONTINUOUS |
Stage 2 | 6 | + | A1 | LIMITS |
| 7 | + | 2 NO HIGH FIRE | |
| 8 | + | 2 C | ENABLE |
| 9 | + | 1 NO LOW FIRE | |
Stage 1 | 10 | + | 1 C | ENABLE |
|
|
|
|
6
7
8
9
10
1
2
3
4
5
an alarm (if the unit is equipped with the alarm option) anytime the safety device senses an abnormal condition.
Figure 5-5_Field installation safety devices
38
| 1 | + | SYSTEM/TANK | |
Intermittent | 2 | + | SENSOR | |
Alarms | 3 | + | B2 INTERMITTENT | |
| ||||
| 4 | + | B1 | LIMITS |
| 5 | + | A2 | CONTINUOUS |
Continuous | 6 | + | A1 | LIMITS |
7 | + | 2 NO HIGH FIRE | ||
Alarms | 8 | + | 2 C | ENABLE |
| 9 | + | 1 NO LOW FIRE | |
| 10 | + | 1 C | ENABLE |
6
7
8
9
10
1
2
3
4
5