All components are located on one board for economy.
Each IC in the DD-4 is plugged into a gold plated IC socket, thus should replacement of any of the IC's be required it is not necessary to return the entire system for repair or upgrade.
Each alarm input is optically coupled to the main board (not directly coupled)
Each of the four alarm channels operates on a set of dry contacts either N/O or N/C contacts. This can be changed by the operator at site or remotely.
The incoming telephone circuit is protected by a sidactor which has the ability to absorb 330 to 600 volts and 150 amps. (This product was not available several years ago). Our system incorporates the latest technology available.
The DD-4 can dial 8 different phone numbers, with up to 16 digits per telephone number. These telephone numbers are stored in non-volatile memory. The customer may elect to dial or not to dial any of the 8 telephone numbers stored in memory.
The DD-4 can dial a telephone number and then deliver a voice message, or it can dial a pager and input a three digit code defining the location and then the active alarms are displayed as numbers 1 to 4.
The DD-4 has 4 individual by-pass switches with corresponding green LED's which show at a glance which channels are in the bypass mode. By-passed channels will not dial out even if the time delay has decremented to zero. It is not necessary to remove wires to disable an alarm trip circuit.
The customer may remotely interrogate the system as to status of the alarms being monitored.
The customer may program the voice messages and alarms messages either locally or remotely utilizing the touch tone telephone included in the DD-4 or the touch tone telephone set at a remote location.
The quality of speech in the DD-4 is comparable to a telephone conversation, not a robotic sound. The customer may enter any sound, language or unusual name with no limit on vocabulary.
All programming is done by telephone hand-set. Digital information is input by way of the keypad and voice messages are input thru the mouthpiece of the telephone set. No special tools or equipment is required to operate or program the unit.
The entire DD-4 system is controlled and operated by a microprocessor. This 40 pin microprocessor is plugged into a gold plated IC socket. Should the needs of the customer change significantly the microprocessor can be replaced with another microprocessor with a different program and the new processor could provide a totally different operation sequence. This change is accomplished by removing the old microprocessor and replacing with the new factory programmed microprocessor.
The DD-4 is a scaled down, consolidated 4 channel version of the ID-4.
Updated 3/98