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2.5.2
PRV Control functions
The unit is shipped from the factory in a low-
power mode referred to as “Shipping
7.1.2). The PRV controller is shipped in a nonactive state, (shown
within IDT
as “No Control”
). The installer must activate PRV control at a suitable point
during installation by putting the device into the “Start Control” state.
The state of the PRV controller operation has no effect on the built-in logger operation.
Operation of the system is described later, in section 2.9.
2.5.3
Controller Description
The Control Box unit directs the operation of the Hydroswitch
unit. The standard configuration includes a flow transducer
input which can be included as part of the decision-making
process that determines the required pressure output. It also
includes pressure measurement interfaces for both upstream
and downstream water pressures. Other interface options can
be included (at the time of ordering).
An example of a Sentinel 2 Control Box is shown opposite.
It contains the following standard interfaces:
•
A connector for attachment of an antenna for the cellular
data network.
•
An electrical MIL-spec connector for the Hydroswitch unit.
•
A MIL-spec connector for communications and the
external battery power option.
•
A MIL-spec connector for flow data.
This measures the rate of flow of water (if a water meter is
available on site to connect to).
(Can be used for control and/or logging purposes).
The example shown contains the following additional interface options
(used for logging purposes only):
•
A quick-release connector for a water-pressure transducer (or an electrical interface
for an external transducer) that usually measures the inlet side of the PRV
(upstream pressure).
•
A quick-release connector for a water-pressure transducer (or an electrical interface
for an external transducer) that usually measures the outlet side of the PRV
(downstream pressure).
