Technical information

1
Control Overview—External Controls Connections
BMS Connections—Burner/Control Disable [151]
Applicable for Vitotronic 300, GW2
Burner Disable:
Dry contact to 151 terminal block.
Primary Consideration(s):
Dry contact disable part of the 120VAC burner call-for-heat circuit.
Opening of the [151] junction will disable the entire control providing a
complete control shutdown.
Configurations:
Burner disable contact wired to terminals 19 and 20.
Notes:
Depending on how the field supplied relay is wired, it may be possible to
disable the burner when the relay is powered or not powered. When
jumper 19 to 20 is removed or disabled, the control does not have the
capability to maintain minimum boiler water temperature or provide
freeze up protection.
1 The [151] plug is plugged into
the boiler control during the
installation process. This plug is
opaque in colour.
2 Two wire conductor between
[151] plug and the DIN rail
mounted terminal block.
3 The [151] terminal blocks are
mounted on the DIN rail
4 One jumper found on the [151]
DIN rail mounted terminal block.
A jumper between terminals 19
and 20 is removed when
installing an emergency
shutdown device.
5 Field supplied relay (dry
contact) to disable burner/
control connected to [151]
terminal block.
Note: Relays used to provide dry
contact disable to [151] terminal
block are controlled by local BMS
or system controller. The relay coil
voltage must be compatible with
the system that is controlling it.
Some examples of this are:
24VAC, 120VAC, 24VDC.
Connections to the [151] terminal
block are part of the 120VAC
control voltage. When open, the
control will experience a complete
control shutdown. Ensure relay
contacts or switch are suitable for
this application.
IMPORTANT
Ensure that all field wiring conforms
to local codes and regulations.
R
2
3
4
IMPORTANT
No minimum boiler water
temperature or freeze-up protection
when control is disabled.
Section 4.2
Section 4
Connection Overview
5346540 v1.0 09/2006 Technical information subject to change without notice
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