Sens SG-A1, User Manual

Page: 13 / 100

SENS.413347.015RE
13
- media are corrosive to the materials of housing;
- power supply voltage mismatching;
- ambient air temperature and humidity not corresponding to operational conditions;
- explosion protection means inappropriate.
During operation, gas detector should be protected from shocks, drops, vibration exposure. It
is prohibited to paint parts of gas detector. It is prohibited to subject gas detector to exposure of
high temperatures and metal spray when welding.
It is not recommended to place gas detector in atmosphere of saturated vapors of petroleum
products for more than 4 hours. When exposed to vapors of petroleum products with concentrations
200% LFL or more, zero recovery time may increase significantly.
When designing system that use SENS SG-A1 gas detector within SI SENS, please consider
the following. Performance of SENS system is determined by time of response (T) of actuating
mechanisms, signaling devices to reaching of specified threshold values by parameters of
measured medium (by concentration) or to occurrence of other events, such as switching of gas
detector to special mode, initiation of failure or exceeding of measurement range.
The response time is determined by number of SENS devices in SENS line and is calculated
using the formula:
T = (600 + 72 • D + 191 • S + 560 • A) ms,
where D - number of sensors (gas detectors SENS SG-A1, level gauges, temperature sensors
SENS PT, pressure sensors SENS PD, etc.);
S - number of displaying instruments (signaling devices MS-K-500-...);
A - number of adapters (LIN-RS232, LIN-RS485, LIN-USB and etc.).
Note - Specified value of T is maximal, real response time - 0...T. Number of signaling
devices is considered to be equal to one, regardless of their number in SENS line, if signaling
devices are configured for "hibernation" mode.
If calculated T time it too large, then to reduce it, apply multiple separated from each
other SENS lines.
Example. SENS system has two gas detectors SENS SG-A1, one multi-channel
signaling device MS-K-500-3 and one adapter LIN-USB. Time T is determined using formula
and is equal to:
T = (600 + 72 • 2 + 191 • 1 + 560 • 1) = 1495 ms ≈ 1.5 s.
8.3 Putting product into operation
8.3.1 In case of big temperature difference between storage conditions and operational
conditions, gas detector received from the warehouse shall be held in operational conditions
for at least four hours.
8.3.2 After prolonged storage or transportation in wet conditions gas detector shall be
dried in normal conditions for at least eight hours.
8.3.3 Before installation of gas detector, carefully read this user manual, perform visual
inspection and check for marking, cable entries fittings, housing integrity, terminal for
connection of external circuits.
8.3.4 The gas detector shall be visually inspected before installation and beginning of
operation. Please draw your attention to:
- absence of mechanical damages, state of protective varnish-and-paint and
electroplated coatings;
- completeness of device according to User Manual;
- absence of detachable or loosely fastened elements;
- marking of explosion protection, warning inscriptions;