Comdial Impact Dsu Instructions Manual

							2.16 Checking The System Installation
The system operating features are set to default conditions at initial power-up. These conditions
provide a basic operating system with a known set of parameters, and you should check out the
system with the default conditions in place. At any time while the system is operating, you can
reset default conditions from station port 10 or 12 following the instructions provided in chapter
3,Programming.
2.16.1 Checking The Resistance
Measure the resistance at the station connector blocks under the following conditions.
·AC power cord disconnected from electrical outlet.
·Common equipment connected to station connector blocks.
·Stations wired and wiring punched down on blocks.
·Bridging clips removed from blocks to isolate stations from common equipment.
Measure the resistance of each installed station and wiring from the station side of the connector
blocks. Resistance values will vary with cable length and station type but should be within the
following limits:
·Greater than 700 KW
2.16.2 Checking The Voltage
Make the following voltage measurements at the station connector blocks under the following
conditions:
·Bridging clips installed
·AC power connected to the common equipment
Measure the voltage across the signal pair. The measured voltage must be within the following
limits:
·28–36 VDC
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							2.16.3 Checking The General Operating Conditions
1. Check the red light emitting diode (LED) system status indicator. Be sure that it is on steady.
If it is off or flashing, refer to the paragraph titledChecking the System Status Indicator.
2. Refer to the user’s guide for operating information and perform a general operational test of
the system by exercising the features from station port 10 or 11. Operational parameters are
per the system default conditions as detailed in Chapter 4 until class of service programming
is performed.
3. Once the basic system is verified as operational, perform the class of service programming as
described in Chapter 3.
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							2.17 Isolating Failures
Section 2.17 will help you to find and identify problems that might occur in the digital telephone
system.
2.17.1 Checking The System Status Indicator
A red LED located on the common equipment cabinet near the music port is the system status
indicator. This indicator light comes on when power is supplied to the system. If the indicator
flashes after power up, it signals that the processor has failed or that the software cartridge is not
installed. Unplug and reconnect the AC power to the power supply and observe the LED
indication. If it still shows a flashing indication, equipment replacement may be necessary.
2.17.2 Testing The Stations
To test the multiline stations for proper operation:
1. Disconnect line cord at station base.
2. On DigiTech telephones, press and hold the MUTE button.
OnImpactand Impression telephones, press and hold 1 on the keypad.
Station will automatically perform self test routine.
3. Release test button as soon as test begins. Sequence of test is as follows:
a. indicators will light in sequence,
b. ringer will sound—be sure volume is set to low or high,
c. indicators and ringer will then turn off at the same time.
4. Replace any station that does not pass the self test.
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							2.18 Installing The System Options And Accessories
This section contains information on installing the battery back up, the analog terminal interface,
and the data interface unit.
2.18.1 Installing The Battery Back Up Assembly
Preparing The Battery Back Up Assembly For Use
The factory ships the battery back up assembly with the harness installed in the enclosure. To
complete the assembly, perform the following operations:
·remove the lid from the metal enclosure and save the retaining hardware,
·install the batteries in the metal enclosure and connect the wiring per the schematic shown
below,
·replace the lid.
You can wall mount the battery back up enclosure if you wish. If you do, follow the same
guidelines and instructions for mounting the common equipment cabinet as set forth at the
beginning of this chapter.
Figure 2–25: Wiring The Batteries
batt3.cdr
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							Figure 2–26: Installing The Batteries
batt1.cdr
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							Connecting The Battery Back Up Assembly
The common equipment provides an interface connector for the connection of an optional
external battery assembly.
CAUTION
Be sure that the AC power cord is connected to the electrical outlet before connecting an
external battery assembly to the common equipment interface connector. This ensures that
internal protection circuitry is operating to prevent damage that could result from improper
connection.
The external battery assembly provides a minimum of one hour of operation should the AC
power to the system be interrupted. The assembly has a 15 ampere-hour current rating and is
fused with the following vaue: 4A 250V 3AG type.
The external battery assembly may include batteries from either of the following suppliers:
·Model PS-12150 from Power-Sonic Corporation, Redwood City CA, 94032
·Model PE12V15 from GS PORTALAC, City Of Industry CA, 91748
The minimum battery backup time for a fully configured system can be calculated using the
formula:
Back Up Time (in hours) =K(15)
1 + [(0.1) (N)]
K (Constant) = 0.9 for G0408 with or without a GM408 module
0.8 for G0816 with or without GM408 modules
0.8 for G1632 with or without GM408 modules
15 = ampere-hours
N = total number of stations
Example:
Assume that a G1632 system plus two GM408 modules are installed along with the optional
battery assembly to provide back-up power.
Back up time =(0.8) (15)
=12
= 2.1 Hours
1+[(0.1) (48)] 5.8
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							During AC operation, the common equipment provides recharging current to maintain the
voltage potential of the external battery assembly at an operational level. The charging circuit
may not provide an adequate charge if an installed battery assembly has a current rating of
greater than 40 ampere-hours. You should measure the battery assembly voltage every three
months.
For proper backup capabilities, make sure the batteries meet the following specifications:
·With a fully-charged battery assembly disconnected from the common equipment, the
measured voltage must be greater than 12 VDC but should not exceed 13.5 VDC.
·With a fully-charged battery assembly connected to the common equipment, the measured
voltage should be less than 13.8 VDC. If the voltage measures higher than this limit,
contact your Comdial Technical Services representative.
·The open output of the common equipment battery charger connection measures 13.6–13.8
VDC. If the charging voltage measures higher or lower than this range, contact you
Comdial Technical Services representative
·An optional external battery assembly requires approximately 10 hours to completely
re-charge to full potential after it has been completely discharged and, in some cases, when
initially installed.
Figure 2–27: Connecting The Battery Back Up Assembly
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							2.18.2 Installing The Analog Terminal Interface
Introducing The Analog Terminal Interface
The ATI-D is a multipurpose,on-premiseaccessory for the digital telephone system. It has dual
circuits that provide the following features:
·INDUSTRY-STANDARD TELEPHONE (IST) INTERFACE—This feature adapts most
industry-standard telephone (IST) devices to the digital telephone system. The ATI-D will
accept both tone (DTMF) and pulse (rotary) dialing from these devices.
·SYSTEM INTERCONNECTION—This feature allows an installer to connect two digital
telephone systems to each other using two ATI-Ds andon-premisewiring.  When
interconnected, either telephone system treats the other telephone system as an IST device.
The two telephone systems are not integrated together and do not share features.
·MODEM ADAPTER—This feature allows the flow of switched data between a data source
and a data receiver through the digital telephone system.
·VOICE MAIL/ANSWERING MACHINE INTERFACE—This feature allows an installer
to connect voice mail systems and automated answering devices to the digital telephone
system.
CAUTION
The ATI-D by itself does not support any off-premise service. Never connect the ATI-D to a
telephone company-supplied line unless you have first installed an acceptable OPX long loop
adapter.
The ATI-D is housed in a self-contained metal enclosure that can be wall mounted if desired.
The ATI-D is powered by the digital telephone system through the station port connections and
employs an internal ringing generator to generate a ringing signal for an IST. Dual, high-quality,
low-loss, balanced, telephone transmission circuitry supports two IST inputs.
One 2-pair cable (four-wire) connects the ATI-D to two common equipment station ports. A
single pair of wires connects the external analog IST equipment to the ATI-D. Modular
connectors are provided to allow quick connections.
Each ATI-D circuit drives a load with a maximum ringer equivalence number (REN) of 2.0, thus
allowing more than one IST connection at each interface input. Check the REN number of the
connected IST equipment so as not to exceed the capacity of the ATI-D. Improper operation
may result if the REN maximum of the ATI-D is exceeded.
The ATI-D supports a wide variety of IST equipment such as 500 and 2500-type telephones,
cordless telephones, voice mail systems, answering machines, FAX machines, and data modems.
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							Detailing The The Analog Terminal Interface Specifications
Power requirements: Supplied by the common equipment
Ringing voltage: 55 VAC Nominal @ 20 Hz
(45 VAC minimum)
Power rated to maximum
REN = 2.0
Battery feed voltage: 24 VDC nominal
Loop current limits between ATI-D
and IST interface: 20 ma min. at 620 ohms
70 ma max. at 0 ohms
DC loop limits from ATI-D to
industry standard interface per port: 620 ohms maximum including interfaced telephony device.
(Approximately 4000 feet with #26 AWG twisted-pair cable
and 300 ohm device load.)
(Approximately 500 feet if two IST devices are connected in
parallel on same tip and ring pair.)
DC loop limits from ATI-D to voice
mail system: Approximately 1000 feet with #26 AWG twisted-pair cable.
Cable insulation resistance: 30,000 ohms minimum
Cable requirement ATI-D to system 2-pair twisted cable; 25 feet maximum length. (Both common
equipment station ports must always be connected to the
ATI-D for every installation, and they must be paired in
sequence — 12 & 13, 14 & 15, etc.)
Cable terminations: 623-type, 4-conductor mini jacks
Dialing: Industry-standard DTMF or Dial pulse (rotary) with nominal
make/break ratio of 40/60 @ 10 PPS
Ringing cadence: Outside calls = 2 second on -
4 seconds off
Intercom calls = Two bursts:
1 second on - .5 second off,
1 second on - 3.5 seconds off
Operating temperature: 32-122 F (0-50 C)
Humidity: 90 % relative, non-condensing
Height: 2.375 inches
Width: 8.062 inches
Length: 11.125 inches
Weight: 4 lbs. (plus 2 lbs.
for packing material)
FCC registered and listed for safety compliance as part of digital telephone system
FCC certified, Part 15 (class A)
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							Mounting The Analog Terminal Interface
Refer to Section 2.1 at the beginning of this chapter for system mounting considerations that are
also applicable to the analog terminal interface.
Mounting Procedure
1. Unpack and carefully inspect the ATI-D for shipping damage. Notify the shipper
immediately of any damage found. Verify that the package contains all parts and accessories
needed for proper installation and operation.
2. If a backboard is required at the mounting location, attach it securely to provide a stable
mounting surface.
3. Use the base of the ATI-D as a template or measure for mounting hole locations per the
dimension details shown in the illustration on the next page.
4. Drill holes of a proper size to accommodate the hardware being used into the mounting
surface. If necessary, prepare these holes with inserts, anchors or other attachment devices as
dictated by the type of mounting surface.
5. Insert the two top screws into the mounting surface and tighten them to within approximately
1/8-inch of the surface.
6. Hang the ATI-D on the top screws using the mounting holes located on the rear of the
cabinet. Note that these holes are elongated with an enlargement at one end. This feature
allows the cabinet to snap down on the screws to secure the mounting when the cabinet is
hung on them.
7. Insert a third screw through the mounting tab located on the lower edge of the cabinet and
into the mounting surface; tighten it into place.
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