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Radio fire alarms, addressable fire alarms and security systems

Title: RFM 5000 RF Carrier Alarm
Description:

Trouble Shooting Guide

RFM 5000 RF CARRIER ALARM

When to use this guide:

Use this guide to find the source of interference that causes the RFM 5000 CD LED to light solid, without turning off, for periods longer than 5 minutes.

Possible sources to investigate (in order):

1. Non-Monaco RF activity from other sources,

2. Faulty RFM 5000, or

3. Stuck Transceiver.

Procedure to follow:

1. Investigate the possibility that non-Monaco RF activity is causing the problem.

a. ACTION: Listen to the speaker on the RFM 5000 and try to identify the audio signals from the speaker, voice, tone, buzzing, etc. If voices are heard the problem is external to the Monaco system. Try to identify the users by listening for call signs and do not focus on looking for a locked transmitter in a Building Transceiver.

b. ACTION: Notify the communications group. They may be aware of a newly installed RF system or extra activities going on at your location that could be using RF equipment causing the interference. They may help pin point the source of the interference.

2. Investigate the possibility that the RFM 5000 may be faulty.

a. ACTION:

i. Disconnect the Antenna Coax Cable from the back of the RFM 5000.

ii. If the CD indication goes away with the cable disconnected and comes back when the cable is reconnected, the source of the interference is coming from outside the ALARM ROOM. NOTE: The coax cable being routed through a TANGLE of other cables is not desirable and can cause the CD LED to light intermittently.

iii. If the CD indication does not go away it could be an RF source within the alarm room or a source very close to the receiver location. (With the antenna disconnected from the RFM 5000 the RF interference signal needs to be very strong to cause the CD LED to light.) Switch out the RFM 5000 with a spare to make sure the problem is not with the RFM 5000. If no spare RFM 5000 is available, switch out the Radio located inside the RFM 5000 (silver metal package).

3. Investigate the possibility of a stuck Transmitter.

a. ACTION: If any AC power failures have occurred, review the printout from the Monaco D-500 central that covers that period of time. List all BT2-3 Building Transceivers that reported AC fails noting each unit that reported a low battery condition and the time between the AC fail message and the low battery message. The BT2-3s that reported a low battery shortly after an AC fail have a higher probability of being the source of the interference signal.

b. ACTION: Perform a manual system poll of the BT2s (from the D-500 central interrogation menu).

c. Note all the NO REPLY BT2s, compare them with the list above and check the units that are on both lists first.

d. ADDITIONAL INFORMATION: If all the NO REPLY BT2s are located in the same general area, the source of the interference is probably in that area. The RF signal (interference) will be strongest near its source and may keep BT2s close to it from replying to the D-500 central poll. If a BT2 is causing the interference, it will not respond to a poll.

e. ACTION: Eliminate each BT2-3 (on the lists developed above) as being the source of the interference. Go to the first BT2-3 and remove all power, both AC and battery, by removing the F1 and F2 fuses on the BT2-3 power supply. (Even if the BT2-3 has all the appearances of being normal, it may be the source of the problem.)

f. If the RFM still has a CD indication, re-apply power to the BT2-3 and move on to the next BT2-3 on your list because this one is not the source of the interference.

g. If the RFM CD indication goes away, re-apply power to the BT2-3.

1. If the CD indication at the RFM 5000 does not return, replace the battery at the BT2-3. Failure to replace the battery will result in more problems after future power outages.

2. If the CD comes back replace the BT2-3.

4. RECOMMENDATION: Use a Monaco SRD to track the source of the interference. This process typically takes less then 30 minutes and requires no special RF skills, only a DC Volt Meter. This option does not work well for interference lasting less than 5 minutes. ACTION FOR SRD USE:

a. Divide the facility into four quadrants. Drive around the base and use the SRD to determine which quadrant has the highest RF signal levels. Drive around that quadrant and narrow the source of the highest signal readings to a few buildings. Look for RF antennas on these buildings.

b. Eliminate each BT2 near the highest signal as being the source of the interference. Go to the first BT2 and remove all power, both AC and battery, by removing the F1 and F2 fuses on the BT2 power supply. (Even if the BT2 has all the appearances of being normal, it may be the source of the problem.)

c. If the RFM still has a CD indication, re-apply power to the BT2 and move on to the next BT2in the area because this one is not the source of the interference.

d. If the RFM CD indication goes away, re-apply power to the BT2.

1. If the CD indication at the RFM 5000 does not return, replace the battery at the BT2. Failure to replace the battery will result in more problems after future power outages.

2. If the CD comes back replace the BT2.

Title: Ensuring Reliable Communications
Description:

ANTENNA MAINTENANCE

When our Product Support Group receives calls from Radio Alarm System customers who have difficulty establishing reliable communication between the Central and a transceiver installed in the field, the solution is most often found by inspecting the antenna installation. The following test of the installed system can help identify the source of the communication problem.

Tools Required:

Digital Multimeter
RF Power Meter with 50 Ohm Load

1) Ensure that the antenna mast and lightning arrestor are properly grounded. See attached drawing for illustration of correct grounding procedures.

2) Perform two forward and reflected power measurements:

a) First, using the 50 ohm "Dummy Load."

b) Second, using the installed antenna system as a load.

3) Results of these measurements should be as follows.

The reflected power should never be greater than 1/10 of the measured forward power. Example: For a measured forward power of 5 watts the reflected power should be absolutely no greater than 0.5 watts. Typically the reflected power should be no greater than 0.2 watts.

4) If your antenna system is marginal or bad, as determined by the forward and reflected power measurement, perform the following.

a) Ensure that all antenna cable connections are clean, tight and free of any corrosion.

b) Ensure that the coaxial cable connection at the base of the antenna is properly weather sealed.

c) Check that all of the antenna elements are installed and the set screws securing the elements are tight.

d) Ensure that the center whip element is "cut" to the correct length for your operating frequency. Every antenna shipped from Monaco Enterprises Inc. is uncut and includes antenna cutting instructions. Contact Monaco Enterprises Inc., if you need to cut the antenna and do not have the cutting instructions.

e) Perform forward and reflected power measurements outlined in step #2.

An open or shorted coaxial cable can also cause communication problems. The following steps describe how to measure the continuity of the antenna cable and connections.

1) Remove power from the transceiver that is being tested. AC power first, then battery power.

2) Disconnect the antenna coaxial cable from the transceiver.

3) Use the Digital Multimeter to measure the resistance from the center conductor to the shield of the coaxial connector.

4) The reading in step 3 should be less than 10 ohms of resistance with the antenna properly connected.

5) Disconnect the cable from the base of the antenna and repeat step 3.

6) This measurement should be an infinite resistance (open).

7) If any of the readings are not as indicated, then inspect the coaxial cable for a broken (open) or shorted (center conductor to shield or ground) center conductor.

Example: If your readings indicate an open conductor, look for loose coaxial connectors, check for an open load coil (resistance measures infinite ohms).

Example: If the readings indicate a short, the most likely cause is a field installed coax termination that shorts the center conductor to the shield.

8) When the above procedure is completed, re-connect the antenna system, both at the transceiver and the antenna.

9) Re-apply power to the transceiver. Verify proper communication by having the BT2 interrogated by the D-500 Plus/D-700 Central Station Receiving System.

Incorporating the above steps in a regular preventive maintenance or inspection program will go a long way towards preventing communication problems.

Title: Ground Fault Troubleshooting Guide
Description: This Product Support Bulletin describes how to troubleshoot an M-1 or M-2 Integrated Radio Transceiver and Fire Alarm Control Panel for Ground Faults. You can download this bulletin by clicking on the word bulletin or request that a copy be mailed or faxed to you.
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