York SSS 14L-B, Руководство по эксплуатации

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JOHNSON CONTROLS
36
FORM 160.00-O2
ISSUE DATE: 04/30/2019
SECTION 8 – MAINTENANCE AND TROUBLESHOOTING
the service technician must understand the system in-
terface, and be able to utilize system wiring diagrams
to follow signal flow throughout the system. Due to the
integration of the LCSSS with the OptiView Control
Center, a good working knowledge of the OptiView
Control Center is also necessary (Refer to ASSOCI-
ATED LITERATURE Forms listed on page 3).
Several levels of documentation are required for the
troubleshooting process. The LCSSS wiring diagram,
supplied with every starter, is the top level document. It
provides the overall wiring and configuration. Sections
of this instruction provide the required lower levels,
specifically, block diagrams provide signal flow and
simplified representations of Logic/Trigger Board cir-
cuitry. The “Inputs and Outputs” of the Logic/Trigger
Board provide details of the required voltage levels at
all connectors.
Begin the troubleshooting process by selecting the ap-
propriate procedure. It is not necessary to sequentially
perform all of them. Perform a procedure only if there
is a problem with that function.
VERIFY SHORTED SCR
1. Remove main input power to the starter.
2. Set ohm meter to Rx1 range. If the ohm meter is a
digital model, and has a diode test scale, place the
meter in the diode test mode.
3. Connect the ohm meter from L1 to T1. If the SCR
is shorted, the ohm meter will display a value less
than 5 ohms. A reading greater than 5 ohms, but
less than 5K ohms may indicate a leaky SCR or
faulty snubber. Such SCRs and snubbers should
be further evaluated.
4. Continue with the other two phases.
5. Replace the shorted SCR Assembly.
VERIFY OPEN OR SHORTED SCR GATE
1. Remove main input power to the starter.
2. Set ohm meter to Rx1 range. If the ohm meter is a
digital model, and has a diode test scale, place the
meter in the diode test mode.
3. Remove the suspected gate connection J6 – J11.
4. Insert the ohm meter probes into the connector.
The meter should display a good value of 10 – 20
ohms in both polarities.
5. If the ohm value is lower than 5 ohms the gate is
shorted, replace the SCR Assembly.
6. If the ohm value is greater than 50 ohms the gate
is open, replace the SCR Assembly.
VERIFY GATE DRIVER OUTPUT
1. Remove main input power to the starter.
2. Set ohm meter to Rx1 range. If the ohm meter is a
digital model, and has a diode test scale, place the
meter in the diode test mode.
3. Remove the suspected gate connection J6 – J11
from the Logic/Trigger Board.
4. Connect the ohm meter negative lead to pin 1
and positive lead to pin 2 of the suspected Logic/
Trigger Board output. The meter should display a
good value of 10 – 20 ohms.
5. Connect the ohm meter positive lead to pin 1 and
negative lead to pin 2 of the suspected Logic/
Trigger Board output. The meter should display a
good value of around 200 ohms.
6. If the ohm value is lower than 5 ohms, the gate
driver is shorted.
7. If the ohm value is greater than 500 ohms, the gate
driver is open. If the values are okay, continue.
8. Reconnect connector J6 – J11. Reapply main in-
put power to the starter.
9. Connect a DC volt meter across the suspected J6-
J11, pin 2 is ground. Without the starter running
a voltage of 0 VDC should be displayed on the
meter. With the starter running, a voltage of .55 –
2.0VDC should be displayed.
10. A higher voltage of around 5 – 10 VDC on the J6
– J11 connector would indicate a poorly conduct-
ing SCR. Replace the SCR Assembly.
11. A lower voltage during the running condition
would indicate a shorted gate on the SCR, or a
bad Logic/Trigger Board. Replace the appropriate
part.