Bulletin No. PAXCK-J
Released 2018-05-15
Drawing No. LP0524
-7-
The option cards are separately purchased optional cards that perform
specific functions. These cards plug into the main circuit board of the meter.
The option cards have many unique functions when used with the PAX.
CAUTION
: The option and main circuit boards contain static
sensitive components. Before handling the cards, discharge
static charges from your body by touching a grounded bare
metal object. Ideally, handle the circuit boards at a static
controlled clean workstation. Dirt, oil or other contaminants that may
contact the circuit boards can adversely affect circuit operation.
WARNING
: Exposed line voltage will be present on the
circuit boards when power is applied. Remove all power to the
meter AND load circuits before accessing the meter.
To
Install:
1.
For option card specific installation instructions, see the installation
instructions provided with the option card being installed.
2. When handling the main circuit board, hold it by the rear cover.
When handling the option card, hold it by the terminal block.
3. Remove the main assembly from the rear of the case by squeezing both
finger holds on the rear cover and pulling the assembly out of the
case. Or use a small screwdriver to depress the side latches and pull
the main assembly out of the case. Do not remove the rear cover from
the main circuit board.
4. Locate the appropriate option card slot location on the main circuit
board. Align the option card terminal block with the slot terminal block
position on the rear cover. Align the option card connector with the
main circuit board option card connector and then press to fully engage
the connector. Verify the tab on the option card rests in the alignment
slot on the display board.
5. If installing an option card that includes a terminal block on the top of
the option card, a knock-out on the top of the PAX case will need to be
removed to allow the top terminal block to be inserted later. Locate the
shaped knock-out that aligns with the option slot for which the
option card is being installed. Carefully remove the knock-out, being
careful not to remove additional knock-outs. Trim knock-out tabs
(gates) that remain on the case. The top terminal block on the option
card will need to be removed before completing step 6.
6. Slide the assembly back into the case. Be sure the rear cover latches
engage in the case. If option card includes a top terminal block, install
top terminal block at this time.
Finger
Hold
Finger
Hold
Serial
Communications
Card
Setpoint
Output
Card
Alignment
Slots
Connectors
Real-Time
Clock Card
Main
Circuit
Board
TOP VIEW
3.0
INSTALLING
OPTION
CARDS
4.0
WIRING
THE
METER
WIRING
OVERVIEW
Electrical connections are made via screw-clamp terminals located on
the back of the meter. All conductors should conform to the meter’s
voltage and current ratings. All cabling should conform to appropriate
standards of good installation, local codes and regulations. It is
recommended that power supplied to the meter (DC or AC) be protected
by a fuse or circuit breaker.
When wiring the meter, compare the numbers embossed on the back of
the meter case against those shown in wiring drawings for proper wire
position. Strip the wire, according to the terminal block specifications
(stranded wires should be tinned with solder). Insert the lead into the
correct terminal and then tighten the terminal until the wire is secure (Pull
wire to verify tightness).
EMC
INSTALLATION
GUIDELINES
Although Red Lion Controls Products are designed with a high degree
of immunity to Electromagnetic Interference (EMI), proper installation and
wiring methods must be followed to ensure compatibility in each application.
The type of the electrical noise, source or coupling method into a unit may
be different for various installations. Cable length, routing, and shield
termination are very important and can mean the difference between a
successful or troublesome installation. Listed are some EMI guidelines for
a successful installation in an industrial environment.
1. A unit should be mounted in a metal enclosure, which is properly
connected to protective earth.
2. Use shielded cables for all Signal and Control inputs. The shield
connection should be made as short as possible. The connection
point for the shield depends somewhat upon the application. Listed
below are the recommended methods of connecting the shield, in order
of their effectiveness.
a. Connect the shield to earth ground (protective earth) at one end
where the unit is mounted.
b. Connect the shield to earth ground at both ends of the cable, usually
when the noise source frequency is over 1 MHz.
3. Never run Signal or Control cables in the same conduit or raceway with
AC power lines, conductors, feeding motors, solenoids, SCR controls,
and heaters, etc. The cables should be run through metal conduit that
is properly grounded. This is especially useful in applications where
cable runs are long and portable two-way radios are used in close
proximity or if the installation is near a commercial radio transmitter.
Also, Signal or Control cables within an enclosure should be routed
as far away as possible from contactors, control relays,
transformers, and other noisy components.
4. Long cable runs are more susceptible to EMI pickup than short cable runs.
5. In extremely high EMI environments, the use of external EMI
suppression devices such as Ferrite Suppression Cores for signal
and control cables is effective. The following EMI suppression
devices (or equivalent) are recommended:
Fair-Rite part number 0443167251 (RLC part number FCOR0000)
Line Filters for input power cables:
Schaffner # FN2010-1/07 (Red Lion Controls # LFIL0000)
6. To protect relay contacts that control inductive loads and to minimize
radiated and conducted noise (EMI), some type of contact
protection network is normally installed across the load, the contacts
or both. The most effective location is across the load.
a. Using a snubber, which is a resistor-capacitor (RC) network or metal
oxide varistor (MOV) across an AC inductive load is very effective at
reducing EMI and increasing relay contact life.
b. If a DC inductive load (such as a DC relay coil) is controlled by a
transistor switch, care must be taken not to exceed the breakdown
voltage of the transistor when the load is switched. One of the most
effective ways is to place a diode across the inductive load. Most
RLC products with solid state outputs have internal zener diode
protection. However external diode protection at the load is always
a good design practice to limit EMI. Although the use of a snubber
or varistor could be used.
RLC part numbers: Snubber: SNUB0000
Varistor: ILS11500 or ILS23000
7. Care should be taken when connecting input and output devices to
the instrument. When a separate input and output common is
provided, they should not be mixed. Therefore a sensor common should
NOT be connected to an output common. This would cause EMI on the
sensitive input common, which could affect the instrument’s operation.
Visit RLC’s web site at http://www.redlion.net/emi for more information
on EMI guidelines, Safety and CE issues as they relate to Red Lion
Controls products.
