Flowline LC90 Remote Controller - Manual (Page 3)

Step Two Step Three
SAFETY PRECAUTIONS SAFETY PRECAUTIONS
About This Manual:
PLEASE READ THE ENTIRE MANUAL PRIOR TO
INSTALLING OR USING THIS PRODUCT. This manual
includes information on three different models of Isolation Remote
Relay Controllers from FLOWLINE: LC90-1001, LC91-1001 and
LC92-1001. Many aspects of installation and use are similar
between the three models. Where they differ, the manual will note
it. Please refer to the part number on the controller you have pur-
chased as you read.
User’s Responsibility for Safety:
FLOWLINE manufactures several models of controller, with dif-
ferent mounting and switching configurations. It is the user’s
responsibility to select a controller model that is appropriate for the
application, install it properly, perform tests of the installed system,
and maintain all components.
Special Precaution for Intrinsically Safe Installation:
DC powered sensors should not be used with explosive or flamma-
ble liquids unless powered by an intrinsically safe controller such
as the LC90 series. "Intrinsically safe" means that the LC90 series
controller has been specifically designed so that under normal con-
ditions the sensor input terminals cannot transmit unsafe voltages
that could cause sensor failure and spark an explosion in the pres-
ence of a specific atmospheric mixture of hazardous vapors. Only
the sensor section of the LC90 is intrinsically safe. The controller
itself cannot be mounted in a hazardous or explosive area, and the
other circuit sections (AC power and relay output) are not designed
to connect to hazardous areas.
Follow Intrinsically Safe Installation Procedures:
The LC90 must be installed in compliance with all local and
national codes, following the latest National Electric Code (NEC)
guidelines, by licensed personnel who have experience in intrinsi-
cally safe installations. For example, the sensor cable(s) must pass
through a conduit vapor seal fitting in order to maintain the barrier
between the hazardous and nonhazardous area. In addition, the sen-
sor cable(s) may not travel through any conduit or junction box that
is shared with non-intrinsically safe cables. For further details, con-
sult the NEC.
Maintain the LC90 in Intrinsically Safe Condition:
Modification to the LC90 will void the warranty and may compro-
mise the intrinsically safe design. Unauthorized parts or repairs will
also void the warranty and the intrinsically safe condition of the
LC90.
IMPORTANT
Do not connect any other devices (such as a data logger or other
measurement device) to a sensor terminal, unless the measure-
ment probe is rated intrinsically safe also. Improper installation,
modification, or use of the LC90 in an installation requiring
intrinsically safe equipment may cause property damage, bodily
injury or death. FLOWLINE, Inc. will not be responsible for any
liability claims due to improper installation, modification, repair
or use of the LC90 by other parties.
Electrical Shock Hazard:
It is possible to contact components on the controller that carry
high voltage, causing serious injury or death. All power to the con-
troller and the relay circuit(s) it controls should be turned OFF prior
to working on the controller. If it is necessary to make adjustments
during powered operation, use extreme caution and use only insu-
lated tools. Wiring should be preformed by qualified personnel in
accordance with all applicable national, state and local electrical
codes.
Install In a Dry Location:
The controller housing is not designed to be immersed. It should
me mounted in such a way that it does not come into contact with
liquid. Its case is made out of PP (polypropylene). Refer to an
industry reference to ensure that compounds that may splash onto
the controller housing will not damage it. Such damage is not cov-
ered by the warranty.
Relay Contact Rating:
The relay is rated for a 10 amp resistive load. Many loads (such as
a motor during start-up or incandescent lights) are reactive and may
have an inrush current characteristic that may be 10 to 20 times
their steady-state load rating. The use of a contact protection circuit
may be necessary for your installation if the 10 amp rating does not
provide an ample margin for such inrush currents.
Make a Fail-Safe System:
Design a fail-safe system that accommodates the possibility of
relay or power failure. If power is cut off to the controller, it will
de-energize the relay. Make sure that the de-energized state of the
relay is the safe state in your process. For example, if controller
power is lost, a pump filling a tank will turn off if it is connected to
the Normally Open side of the relay.
While the internal relay is reliable, over the course of time relay
failure is possible in two modes: under a heavy load the contacts
may be “welded” or stuck into the energized position, or corrosion
may build up on a contact so that it will not complete the circuit
when it should. In critical applications, redundant backup systems
and alarms must be used in addition to the primary system. Such
backup systems should use different sensor technologies where
possible.
While this manual offers some examples and suggestions to help
explain the operation of FLOWLINE products, such examples are
for information only and are not intended as a complete guide to
installing any specific system.