3
UR21S-MOI-IT-W-ML-10-22-Rev0
Watts Water Technologies, Inc.
EN
Note
Note
(1)
: Some Detectors of the DR-UR.21.S-EXR type, ie equipped with Display Board with Relay (prefix DR-), with extended temperature range (suffix
-EXR) and which use Catalytic or Infrared sensitive elements, ie with particular absorption characteristics, have temperature class T5 instead of T6.
Note
(2)
: Detectors using Catalytic Sensing Elements are sensitive to all Flammable Gases, with different sensitivities and responses related to Methane
Gas (see Tables contained in the Display Board and Service Terminal Manuals), through which these relative responses can be inserted in the Detector.
Note
(3)
: When Detector detects a very high gradient of increasing concentration, and the full-scale value of 20% is exceeded, power is removed from
the sensing element and the out-of-range (fault condition for overrange) is declared respectively with:
•
the 4÷20mA output which is set at 22mA;
•
fault relay output activated (relay energized or not depending on the selection made);
•
the status LED visible from outside fixed on with an OFF flash of 0.5s every 5s
display (if present), explicitly declares the need for a recalibration.
After such a condition occurs:
•
make sure the area is free of explosive mixtures;
•
turn off and turn on the detector to allow the sensing element to be powered and wait at least an hour to allow thermal stabilization.
Only entering the calibration procedure can bring the detector to exit the overrange fault state.
As with all other operational contexts:
•
if the recalibration procedure is successful, it can bring the detector into normal operating status;
•
if the recalibration procedure is not successful, the detector is simply declared faulty.
4 Relay SPDT Card UZR20.4(
4
)
It is used to activate signals and/or external
systems (light signals, sirens, ventilation
systems, etc.).
Note (
4
): not insertable if the Display Board DR… or DN… is present
NO or NC contacts available, selectable by
jumpers.
(default values for explosion gas and CO)
N. 4 LEDs are presente and associated
with the status of each Relay and separate
quick-connecting term. blocks
Relay A: Pre-alar (10% LEL, 50 ppm)
Relay B: 1st Thresh. Alarm (20% LEL, 100 ppm)
Relay C: 2nd Thresh. Alarm (40% LEL, 200 ppm)
Relay D: Detector Fail
The state of the LEDs is directly associated
with the status of the relative Relay: Relay X
“On” => Led X “On”.
Alarm intervention thresholds can be reset by dip-switch (12
combinations) or by service and maintenance terminal or display.
Relay contact range:
50mA @ 24Vac/dc, 100mA @ 12Vac/dc
Relay control logic:
•
Direct: Relay ON in the presence of an event;
•
Inverse: Relay ON in the absence of an event.
Display Board without Relay DN-DetName.
Display Board with Relay DR-DetName.
Display Boards are in fact the Operator
Interface on board the Detector for control,
monitoring and calibration operations. They
manage:
N. 4 Push Buttons used to give the
operator commands;
N. 4 SPDT Relay (only for DR .. Board)
Each Relay is associated with a Led for
the local Alarm or Sensor Fault signaling
The state of the Leds is associated directly
to the status of the relative Relay: Relay X
“On” = > Led X “On”
N. 6 heating resistors for Extended Range
Detectors
(suffix -EXR to the name of the detector)
PhotoMOS Card UZS20..
UZS20.E Normal Pre-Al 1
st
Th 2
nd
Th Fail
22kΩ 10kΩ 2,2 kΩ n.p. Open
It is used to indicate the status of the
detector through a resistive value presented
at the terminals.
UZS20.A Normal Pre-Al 1
st
Th 2
nd
Th Fail
27kΩ n.p. 10kΩ n.p. Open
It is typically used in conjunction with
modules that put on the LOOP peripheral
fire alarms that have a behavior similar to
that of smoke detectors.
UZS20.S Normal Pre-Al 1
st
Th 2
nd
Th Fail
2,2kΩ n.p. Close n.p. Open
Sensor Lifetime
Sensor average lifetime (see technical characteristics) is referred to a typical usagwe in a pollution-free environment. Presence of
a high concentration of pollutanwts can shorten the lifetime of the sensing element.
The Catalytic Sensor only works in the presence of Oxygen. Do not use pure gas or the lighter directly on the Sensor which
could be irreparably damaged.
CAUTION: consider that in particularly polluted environments or with vapors of flammable substances (in particular solvents), the
useful life of the sensor can be considerably reduced. Some Substances cause a permanent reduction in sensitivity, preventing
