MSA ZGARD S - Page 7

Section 3
ZGARD S & DS Sensors
General Information
OPERATING SPECIFICATIONS
Detection Range CO - Carbon Monoxide, 0-100 or 0-200ppm
Principal of Operation SS, Semiconductor OR EC, Electrochemical
Detection Range NO2 - Nitrogen Dioxide, 0-10ppm
Principal of Operation
EC, Electrochemical
Detection Range R11, R12,R22 or R134a - Refrigerants, 0-1,000ppm
Principal of Operation
SS, Semiconductor
Detection Range NH3 - Ammonia, 0-500ppm
Principal of Operation
SS, Semiconductor
4-20mA Output Sensors
Operating Power
24Vdc, 100mA used with MSA ZGARD C Series Controllers
Connection
3-wire point-to-point connection
RS485 Digital Output Sensors
Operating Power
24Vdc, 100mA used with MSA ZGARD C Series Controllers
Connection
RS485, 4-wire network connection
Digital Addressing
Network Address jumpers, 1 to 127
4-20mA, Stand Alone Sensors
Operating Power
24Vdc, 100mA used with commercial DCS and PLC devices
24Vac, 100mA used with commercial DCS and PLC devices
Connection
3-wire point-to-point connection
Status LED Indicator
Sensor OK
Temperature
Operating: 0° to 40°C (32° to 104°F): Storage: -10° to 50°C (14° to 122°F)
Accuracy
Solid-State (SS) Sensors +/- 5%, Full Scale (FS)
Electrochemical (EC) Sensors +/- 2%, Full Scale (FS)
Humidity
0 to 95% RH
ZGARD S Enclosure
Standard, Plastic double-gang connection box with metal front cover
(Optional) NEMA 4X Fiberglass design OR Metal housing and cover
Dimensions
5.5” H (140 mm) x 5.5" W (140 mm) x 2.2" D (56 mm)
Weight
0.45kg (1.00 lbs.)
ZGARD DS Enclosure
Standard, NEMA 4X Fiberglass
Dimensions
7.0” H (178 mm) x 10.5" W (267 mm) x 4.5" D (114 mm)
Weight
1.1kg (2.45 lbs.)
Certification
ENTELA (to CSA Standards)
Sensor Outputs: The ZGARD S & DS Sensors provide
two sensor output options, a 4-20mA analogue output or
a RS485 digital signal. The ZGARD S & DS, RS485
sensor includes an identifiable digital signature
recognized by any MSA ZGARD C Series Controllers.
Sensing Technology: Toxic gasses are detected by way
of electrochemical cells, for targeting the gas of interest
and resolution. Moreover, second generations of semi-
conductor detectors offer a highly effective solution for a
variety of different applications.
LED Status: The Sensor OK LED is OFF for 30 seconds
upon power-up and will turn ON indicating that the device
is operating properly.
Onboard Communication Test: The ZGARD S (SS)
sensors provide a means of driving the output to 50% or
100% full-scale. The ZGARD S & DS (EC) sensors
provide a means of driving the output to 0% or 100% full-
scale. When the onboard test jumpers are inserted, the
sensor generates the selected output signal. This feature
is useful for testing remote devices, which may be
connected to the sensor output.
Enclosures: The standard ZGARD S sensor is housed in
a surface mount tamper resistant plastic enclosure. There
are two additional enclosure options, Metal housing and
cover plate or Fiberglass NEMA 4X housing. The
standard ZGARD DS sensor is housed in a Fiberglass
NEMA 4X housing.
Cut-Off Feature: The solid-state (SS) versions provide a
cut-off feature to eliminate possible high background
interferant's. This function is factory set to enable and is
also jumper selectable.
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