Schweitzer Engineering Laboratories SEL-352-1 - Main Board; Output Contact Jumpers

2-18 Installation Date Code 20010731
SEL-352-1, -2 Instruction Manual
3. Loosen the six front-panel screws (they remain attached to the front panel) and remove the
relay front panel.
The relay contains devices sensitive to electrostatic discharge (ESD).
When working on the relay with front or top cover removed, work
surfaces and personnel must be properly grounded or equipment
damage may result.
4. Each circuit board corresponds to a row of rear-panel terminal blocks or connectors and is
affixed to a draw-out tray. Identify which draw-out tray needs to be removed. An SEL-352
Relay Model 0352x0 has only a main board. A Model 0352x1 or 0352xY relay has an extra
I/O board below the main board.
5. Disconnect circuit board cables as necessary so you can remove the board and draw-out tray
you want. To remove the extra I/O board, first remove the main board. Remove ribbon
cables by pushing the extraction ears away from the connector. Remove the six-conductor
power cable by grasping the wires near the connector and pulling away from the circuit
board.
6. Grasp the drawout assembly of the board and pull the assembly from the relay chassis.
7. Locate the jumper(s) or battery to be changed. Make the changes you want. Note that the
output contact jumpers are soldered in place.
8. When finished, slide the drawout assembly into the relay chassis. Reconnect the cables you
removed in step 5. Replace the relay front-panel cover.
9. Replace any cables previously connected to serial ports.
10. Reenergize the relay by reconnecting wiring to rear-panel terminals + (Z25) and – (Z26). On
Connectorized versions, replace the power connector at rear-panel terminals + (Z25) and
– (Z26).
Main Board
Output Contact Jumpers
Refer to Figure 2.16 to see the layout of the main board and locate the solder jumpers to the rear
of the output contacts. Select the contact type for the output contacts. With a jumper in the A
position, the corresponding output contact is an “a” output contact. An “a” output contact is
open when the output contact coil is de-energized and closed when the output contact coil is
energized. With a jumper in the B position, the corresponding output contact is a “b” output
contact. A “b” output contact is closed when the output contact coil is de-energized and open
when the output contact coil is energized. These jumpers are soldered in place but may be
changed in the field.
Note that the ALARM output contact is a “b” contact and that the other output contacts are all
“a” contacts. This is the normal configuration of these jumpers in a standard relay shipment.
The additional I/O boards have slightly different layout locations for the jumpers relative to the
corresponding output contacts.
1.
CAUTION
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