Ingersoll-Rand Intellisys SSR 10-40, Руководство для обслуживающего персонала

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The compressor will shut down and the display will indicate the specific sensor
in an alternating message with whatever message was on the display at the
moment the Alarm condition began. These messages will continue to alternate
until the problem is corrected and "Reset" is pushed.
If an open circuit condition is experienced on the Package Discharge Tempera-
ture Sensor (4ATT), the compressor will not shut down but "Warn" and "Reset"
will appear at the lower edge of the panel and the message display will show
Sensor Failure 4ATT alternately with whatever message was on the display at
the moment the "Warn" condition began.
The panel will not Reset until such time as the problem is corrected.
B) An Open Circuit with the Ground wire on any of the three temperature
sensors will not create a problem to cause either a "Warn" or "Alarm" condition.
In reality, this ground wire is one end of a shield for the Black and White wires
to reduce electrical interference (noise) that could cause incorrect readings.
One end of the shield goes to ground while the other end located within the
temperature sensor housing is an open circuit in relation to the sensor housing.
C) Black Wire to Ground conditions cause a direct short of the 5 volt DC Barrier
Board power supply. This direct short circuit rarely damages the Analog Board
or other components and merely pulls the output signal of the voltage regulator
down to a point at which the components are unable to function. Correcting the
short circuit condition will in almost every instance, correct the problem.
Prior to making a series of checks for a black wire to ground condition, verify that
the Analog Board has 9 volts DC supplied to it using the following procedure.
1) Observe the small voltage regulator "VR1" on the upper left corner of the
Analog Board. This voltage regulator is held in position by a small hexagon
shaped nut.
On the lower edge of this voltage regulator can be found three connection points.
2) Use a voltmeter between the LEFT - bottom connection point of the voltage
regulator and any of the "GND" (ground) terminals of the top-most terminal strip
BTS1. The voltage measured between these two points should be approxi-
mately 9 volts DC.
3) If voltage is measured as outlined in Step 2, proceed to check the voltage
regulator output by measuring between the RIGHT - bottom connection point
and any of the "GND" (ground) terminals of the top-most terminal strip BTS1.
The voltage measured between these two points should be approximately 5 volt
DC.
If the 5 volts DC supply for the Analog Board is interrupted for any reason to
include a direct short circuit condition, the compressor will shut down in an
"Alarm" condition.
If this ground condition exists on the Black wire going to any of the three
temperature sensors, the panel display will show "Scroll for Alarm" then "Press
Test for Values" then "Press Reset 2 x - Clear" in an alternating message list.
Also, Reset, Test, red UP arrow, red DOWN arrow and "Alarm" are on the lower
edge of the panel.
After correcting the ground condition, press "Reset" to clear the panel.
D) Black Short Circuited to White causes the particular temperature sensor
to display "246 DEG" on the Intellisys panel if that display has been selected.
This problem will cause an Alarm shutdown on the Airend Discharge Tempera-
ture sensor 2ATT only. When scrolling for the cause of Alarm, "246 DEG" will
show on the display for "Airend Discharge Temperature".
Temperature sensors 2CTT and 4ATT do not cause an Alarm or Warn condition
and therefore only show 246 DEG on the display if the Black and White wires
become short circuited.
As an example, if the Black and White wires for Package Discharge Tempera-
ture sensor 4ATT become short circuited, the compressor will continue to run
and "246 DEG" will come up on the display for Package Discharge Temperature
when selected.
The short circuit condition is individual to the affected sensor and will not cause
multiple displays on the panel.
E) White Wire to Ground will cause a "Warn" condition for "Package Discharge
Air Temperature" sensor 4ATT while the compressor continues to operate. The
Intellisys display will alternate "Sensor Failure 4ATT" with whatever was on the
display at the moment the warn condition began. Remember, the compressor
continues to run with only a "Warn" indication and "Reset" along the lower edge
of the panel.
If a short circuit develops between the White wire and Ground on "Injected
Coolant Temperature" sensor 2CTT, the compressor will shut down with an
"Alarm" condition.
The display will show "Sensor Failure 2CTT" followed by "Coolant Temp",
"Press Test For Values" followed by "Press Reset 2 - Clear".
If a short circuit between the White wire and Ground develops on "Airend
Discharge Temperature" 2ATT, an "Alarm" will occur and the compressor will
shut down.
The Intellisys display will show "Airend Disch Temp" followed by "Press Test for
Values", and "Press Reset 2 x - Clear" and "Sensor Failure 2ATT".
An investigation of the wires is now indicated.
After the short circuit condition is corrected, the Intellisys can be cleared in the
normal manner.
In summation, wire damage is the most likely cause of temperature sensor
failures. These failures are usually "cut wires" or "short circuits" either to ground
or between wires. A careful investigation will quickly identify your problem area.