Det-Tronics NTMOS IP66/IP67 H2S Gas Detector User Manual
Page 4

95-8670
2.1
2
DETECTOR OUTPUT
The non-isolated 4-20 mA dc drive circuitry is rated at a
maximum 600 ohms loop resistance with 24 Vdc supply
voltage.
DET-TRONICS OPTIONAL JUNCTION BOXES
When not connected directly to a transmitter/control
device, the NTMOS Gas Detector can be connected
to a Gas Detector Termination Box (GDTB) Termination
Box. The GDTB contains a circuit board with the required
connectors for proper field wiring, as well as an internal
magnetic switch for non-intrusive detector calibration and
an LED to indicate calibration status. Refer to the GDTB
instruction manual (95-8644) for complete information
regarding the GDTB.
DET-TRONICS DISPLAYS/TRANSMITTERS
The NTMOS Gas Detector integrates easily with the
following Det-Tronics transmitters:
FlexVu Model UD10
The FlexVu UD10 Display Unit provides the approved
function of a low concentration gas controller for the
NTMOS Detector. The UD10 is designed and approved
as a stand-alone controller when connected to a certified
gas detector, such as the NTMOS, and performs all the
functions of a gas controller.
Gas concentrations are displayed on an alphanumeric
display in PPM. The UD10 provides a linear isolated/
non-isolated 4-20 mA DC output signal (with HART)
that corresponds to the detected gas concentration or
indicates a fault condition.
All electronics are enclosed in an explosion-proof
aluminum or stainless steel housing. The display unit is
used with a single detector that may be either coupled
directly to the UD10, or remotely located using a Sensor
Termination Box model STB or GDTB.
The UD10 features non-intrusive calibration. A magnet
is used to perform calibration as well as to navigate the
internal configuration menu. Refer to the UD10 instruction
manual, 95-8618, for complete information regarding the
FlexVu UD10 Display Unit.
U9500 Infiniti Transmitter
The U9500B Infiniti
®
transmitter is a single channel
device. In addition to the standard 4-20 mA analog
signal output, the U9500B offers 4 optional relay outputs
for fault and alarm indications. The 4 outputs are: fault,
high alarm, low alarm, and auxiliary alarm. The relays
have form C (SPDT) contacts. The alarm relay contacts
are selectable as a group for latching or non-latching.
During normal operation, the fault relay is non-latching,
but for initialization faults, the fault relay latches. The
alarm relays are also selectable, as a group, for normally
energized or de-energized (no alarms). The fault relay is
always normally energized (no fault). Refer to the Infiniti
Transmitter instruction manual, 95-8444, for complete
information regarding the transmitter.
INSTALLATION
CAUTION
The wiring procedures in this manual are intended
to ensure proper functioning of the device under
normal conditions. However, because of the
many variations in wiring codes and regulations,
total compliance to these ordinances cannot be
guaranteed. Be certain that all wiring complies
with applicable regulations that relate to the
installation of electrical equipment in a hazardous
area. If in doubt, consult the authority having
jurisdiction before wiring the system.
IMPORTANT
Considering that H
2
S is heavier than air, and in
order to maintain IP66/IP67 Ingress Protection
rating, the detector must be mounted vertically at a
maximum height of 18 inches from surfaces below.
NOTE
The NTMOS Detector shall be connected to a
performance certified low concentration gas
controller, with latching alarms.
CAUTION
Exposing the NTMOS Detector to silicones will
dramatically reduce its sensor response and
sensor life, and must be avoided.