System Sensor DH500ACDC - Manual (Page 10)

Ion Units
9.
See Figure 11. Remove the cover and screen assembly
by depressing the three lock prongs on the top of the
cover and rotating the cover counterclockwise. The
CRT400 Cover Removal Tool makes cover removal eas-
ier.
10. Carefully pull the screen out of the cover.
11. Clean the screen thoroughly with a soft brush or vacu-
um cleaner (replacement screens, part no. RS14).
12. Brush or vacuum the inside of the cover. The cover
may then be blown out using clean compressed air.
13. Vacuum the sensing chamber before using clean, com-
pressed air to loosen and blow out any remaining
debris.
14. Press the screen back into the cover.
15. Replace the detector cover on the sensing chamber.
Rotate it clockwise to lock it in place.
Both Types Of Units
16. Reinstall the detector in its housing.
17. Restore system power.
18. Put detector into alarm using appropriate method
described in STEP 7.
Perform Detector Check
19. Notify the proper authorities that testing has been
completed and the smoke detector system is back in oper-
ation.
20. Other checks that should be made during maintenance
procedures:
— Holes or cracks in duct work near vicinity of detec-
tor.
— Air leaks where detector housing or sampling tubes
are attached to duct.
— Dust accumulations in or on sampling tubes.
— Wiring terminal screw tightness.
Accessories Part No.
Remote LED RA400ZA
Piezo Alert Sounder PA400
Replacement Filters F36-05-00
Magnet M02-04-00
End Plug For Sampling Tube P48-21-00
Installation Kit (Parts bag) A2650-01
Ionization Replacement Screen RS14
Sensitivity Test Kit MOD400R
Ionization Cover Removal Tool CRT400
Remote Test Station RTS451/RTS451KEY
Programming Specifications/Requirements For
Intelligent System Control Panels
Models 1551 and 2551 can be used with the DH500ACDC if
the following constraints are observed.
1. There may be a limit to the number of devices per zone
that can have their LEDs latched on. The number of
devices is determined by the control panel and its abili-
ty to supply LED current. If more than the maximum
number of devices is on the same loop, do NOT use the
DH500ACDC for control purposes. Control for duct
applications would need to come directly from the con-
trol panel or by using control modules.
2. The duct control circuitry (auxiliary relay contacts and
auxiliary alarm output) may change states if the sensor
is tested and the LED is turned on for more than 4 sec-
onds. If the LED is latched on for less than 4 seconds,
the control circuitry of the DH500ACDC will NOT oper-
ate.
3. The panel must not poll the same unit for more than 4
seconds continuously or the auxiliary relay and auxiliary
alarm output may switch states. After 4 seconds of con-
tinual polling of a device, the panel must wait a mini-
mum of 100ms before polling or communicating to that
same device.
4. Communications must not cease for more than 3 sec-
onds without an additional clock pulse (after Pulse
Width 5) to turn off the LED on the sensor.
5. To allow the auxiliary relay and auxiliary alarm output
to return to a standby condition, (after being in alarm)
the panel must wait a minimum of 100ms after turning
off the sensor LED before communicating to that device
again.
CAUTION
D500-07-00 10 I56-432-11R