CleaverBrooks Hawk 1000, Operation Manual

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Section 2 — System Components Hawk 1000
2-6 Part No. 750-366
2.5 Sensor Inputs
The following table shows the sensors available as standard and as options for steam systems (ST) and for
hot water (HW) systems:
All systems use RTDs with a transmitter to produce 4-20mA output for temperature detection.
2.5.1 Steam Systems:
Steam Pressure is the primary sensor input to the HAWK 1000 Controller in a Steam System. It transmits a
4-20mA process variable signal to the Controller that is used to control Firing Rate and the Operating Limit
Control.
Stack Flue Gas Temperature is used for High Stack Temperature alarms and shutdown. It is also used in the
boiler efficiency calculation.
Water Temperature (mandatory on steam boilers) measures boiler-shell water temperature and is used for
thermal shock protection and hot standby control on steam boilers. The standard location for the thermowell is
a 1/2” NPT coupling at the right-hand side center-line of the boiler shell. If this location is not available, an
unused feedwater connection may be used.
Water Level sensor is OPTIONAL on steam boilers, but must be a CB Level Master.
2.5.2 Hot Water systems:
Supply Temperature is the primary sensor input to the HAWK 1000 Controller in a Hot Water system. It
transmits a 4-20mA process variable signal to the Controller that is used to control Firing Rate and the
Operating Limit Control.
Outdoor Temperature is used in Hot Water Systems with the Outdoor Temperature Reset Option.
Return Temperature is used in Hot Water Systems with the Return Temperature option and is monitor only.
NOTE: The Outdoor Temperature and Return Temperature sensors use the same input. One or the other can
be used with the Hawk 1000, but not both.
Sensor System Standard Optional
Steam Pressure ST Yes
Stack Temperature ST & HW Yes
Water Temperature ST Yes
Water Level ST Yes
Supply Temperature HW Yes
Outdoor Temperature HW Yes
Return Temperature HW Yes