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2.4. Boiler Conductivity
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the conductivity sampling method.
Timed sampling
incorporates a sample timer which allows the boiler to be sampled at periodic intervals.
Sample intervals are adjustable from 1 minute to 99 hours, 59 min. Sample duration (on-time) is adjustable
from 1 second to 99 minutes, 59 seconds.
Sample and hold
uses a sample timer for periodic sampling intervals. The unit will sample for its duration
and then hold the blowdown valve closed for a settable period (hold time). The conductivity is checked at
the end of the hold period, if additional blowdown is required the blowdown valve is held open for a preset
amount of time (blowdown time). Then sample cycle is repeated.
Pulse Sample
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water instead of the sample interval timer.
Continuous sample
has a sample of boiler or condensate water go past the probe continuously. If the
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SET POINT
- What reading turns the relay on
DIFFERENTIAL
- Amount reading changes by before
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HIGH ALARM
- What reading generates a High alarm
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LOW ALARM
- What reading generates a Low alarm
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2.5. Aux Inputs
Auxiliary inputs are the digital inputs for optional Flow Switch and other digital inputs such as low drum level
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both or none.
Note:
Digital inputs can have the direction selected
between OPEN or CLOSED as the alarm polarity. If
set for CLOSED the input will be in alarm when it sees
a closed contact.
