Vodavi Starplus Dhs/dhs-e Technical Manual

							1-4Toll Fraud and DISA Disclaimer 
						

							2
DHS Description
and Installation
The STARPLUS DHS/DHS-E™ Digital Hybrid System is a full-featured digital key
telephone system. The common system architecture supports three digital
telephone models, a Direct Station Selector (DSS)  and an expandable analog
adaptor interface. The 
DHS is designed to meet the telecommunications needs of
small-to-medium sized business offices. 
						

							DHS General Description2-1
DHS General Description
System Technolog y
The DHS product line incorporates state of the art digital technology for voice switching 
and call processing utilizing Pulse Code Modulation and Time Division Multiplexing 
(PCM/TDM). The DHS  family is engineered to allow migration of the DHS digital terminals 
and terminal accessories throughout the entire product line. ISDN-like, 2B+D technology 
complements the system architecture and capabilities. On one industry standard twisted 
pair, key telephones perform all system functions and voice communications. Some 
additional features of the DHS  include:
†A non-blocking switch, with no loss or degradation of voice signals.
†Stored-Program Control (SPC), utilizing a 16-bit, 8 MHz microprocessor.
†Memory consists of 512 KB of Read Only Memory (ROM) and 128 KB of Random 
Access Memory (RAM).
When an analog device interface is required, a 2-Port Central Office (CO) Module may be 
connected to any one digital station port. The 2B+D technology allows the DHS  to split 
one digital key telephone port voice channel (B1) and the second voice channel (B2) to 
provide two independent SLT-type device interfaces. 
The 2-Port CO Module may be expanded with the 2-Port Analog Expansion (in the 2-Port 
CO Module housing). 
The 2-Port CO Module and 2-Port Analog Expansion each require one dedicated digital 
station port.
System Components
KSU Components
The DHS platform is comprised of three key telephone models, an optional Direct Station 
Selector (DSS) and a modular Key Service Unit (KSU) which houses the following KSU 
components:
†3 x 8 Module
†Standard MOH/BGM Module
†6-Port CO Module
†Option Module
The application of analog devices in the DHS has the effect of two-to-one 
port gain. For every single digital port used to interface a 2-Port CO Module/
Expansion, two analog ports are available. 
						

							2-2DHS General Description
Two 3 x 8 Modules may be added to the initial 3 x 8 module in the Basic KSU. Alternately, 
a 6-Port CO Module may be substituted for one 3 x 8 module for greater flexibility. The 
maximum capacity is either 9 CO lines x 24 stations, or 12 CO lines x 16 stations. 
The basic KSU is equipped with a Standard Background Music/Music-On-Hold (BGM/
MOH) Module. An external music source may be connected to this interface via a 1/8 in. 
phono plug for BGM/MOH listening. The Option Module replaces the Standard BGM/
MOH Module and provides two DTMF receivers and two Tone Detectors specifically for 
ECF, DISA, Unsupervised CO Line Conference, and Dial Tone Detection.
External Components
†Executive Key Telephone
†Enhanced Key Telephone
†Basic Key Telephone
†2-Port Analog Adapter
†2-Port SLT Expansion
†Direct Station Selector 
Table 2-1: System Configurations
Equipment InstalledMaximum Number of 
Loop Start LinesMaximum Number of 
DHS Digital Key
Telephones
One 3 x 8 module 3 8
Two 3 x 8 modules 6 16
Three 3 x 8 modules 9 24
One 3 x 8 module and
One six-port CO module98
Two 3 x 8 modules and
One six-port CO module12 16
SLT operations do NOT use Option Module resources.
Key telephones are available in two colors: Off White, and Charcoal Gray. 
						

							DHS General Description2-3
System Administration
The system default customer data base can be entered and changed, under password 
control, from any Executive Key Telephone. All Customer information is protected by an 
internal rechargeable NiCad or NiMh battery. Programmable password protection is 
allowed for each station, system administrator and external (DISA) callers. An optional PC 
Programming Software is available to program the DHS  system. This Software allows the 
user to program offline and then upload directly to the system. The DHS requires the 
Option Module to use the PC Programming Software.
Key Service Unit (KSU)
The DHS Key Service Unit (KSU) is a modular flat-pack design. It is a self-contained cabinet 
with internal power supply, common control circuits (CPU board) and 3 x 8 module. The 
power supply AC transformer is hard-wire selected for either 117V AC (
+10%). The KSU is 
designed for wall mount and shipped with a wall mounting template. The compact KSU 
weighs less than 20 pounds and is UL compliant.
Standard inserts installed over various KSU openings may be removed or repositioned to 
accommodate exterior connection requirements; three such panels are present. One may 
be removed to route a serial cable through the KSU outer housing for connection of 
SMDR equipment. Another may be removed to route a serial cable through the KSU outer 
housing for connection of a modem or PC (via a straight-through cable). This serial port is 
used for Caller ID, PC programming and maintenance. Both serial ports are provided 
when the Option Module is installed.
One KSU opening panel may be removed or repositioned to accommodate cable entry 
requirements through the outer housing for connection to the MDF.
Figure 2-1: DHS Unit (cover removed) 
						

							2-4DHS General Description
Power Supply
The power supply circuitry of the DHS  incorporates a linear design transformer with a 
choice of input voltage taps. The transformer primary windings are shipped wired for 
117V AC applications; a factory insulated tap wire may alternatively be connected for 
230V AC applications. Since the power supply is linear in design the output voltage varies 
between 21.6 and 32V DC depending on load and stability of the input voltage. The 
output voltage is delivered to the CPU board for distribution and rectified there for logic 
and control voltages.
Two fuses are equipped on the power supply board, one for AC input over-voltage 
protection and one for DC output over-voltage protection. A Double Pole Double Throw 
(DPDT) switch is accessible from outside of the KSU when the KSU cover is in place. The 
DPDT switch will simultaneously switch AC input and DC output circuits ON and OFF.
In the event battery backup operation is desired and equipped via the optional DHS 
Battery Charging Unit (BCU), the KSU switch may be used to switch OFF/ON power from 
both sources.
The power supply wiring harness is equipped with a mate-n-lock connector on the DC 
output for connection of the DHS  BCU. When equipped, the BCU will maintain complete 
system operation during commercial power outages. A current draw/configuration chart 
is included in this document for assistance in selecting the appropriate batteries for use 
in the BCU. Please consult the BCU manual for installation precautions and proper battery 
installation.
Central Processor Unit (CPU)
The CPU board is standard in the KSU. This board contains all circuitry required to control 
the fully-equipped DHS . Three bus connectors are provided where the station/CO line 
interface 3 x 8 module and 6-Port CO Module are connected. The Option Module 
connector and Standard MOH Module connector are also located on the CPU board. All 
digital voice switching and call process data switching is accomplished on the CPU board. 
3 x 8 Module
The 3 x 8 module provides interface of three loop-start CO lines and eight DHS key 
telephones.
Each CO line circuit incorporates over-voltage protection, ring detector, loop detector, 
loop/pulse-dial relay, current sink circuit, coupling/isolation transformer (impedance 
600:Ohms), hybrid circuit and combo (CODEC and filter) polarity guard circuit and radio 
frequency noise filter.
Each digital key telephone port is comprised of a proprietary transceiver designed using 
ISDN type 2B+D architecture.
Physical connection of stations and CO lines to the 3 x 8 module is made through one 
male 25-pair, amphenol-type connector to the Main Distribution Frame (MDF). Station 
power and signaling to the digital key telephones are provided via a single twisted pair 
from the 3 x 8 module. 
						

							DHS General Description2-5
Figure 2-2: 3 x 8 Module
6-Port CO Module
The 6-Port CO Module may be installed in place of a 3 x 8 module in the last card position. 
The 6-Port CO Module interfaces with 6 loop-start CO lines. No digital station interface is 
provided on this module. The 6-Port CO Module is shipped with four mounting stand-offs 
used to install the board into the Basic KSU, two 6-conductor modular line cords and two 
6-conductor modular blocks. The mounting cords and modular blocks are used to extend 
the CO line interface circuits to the MDF for connection.
Each CO line circuit consists of an over-voltage protector, ring detector, loop detector, 
loop/pulse-dial relay, current sink circuit, isolation transformer, hybrid circuit and COMBO 
(CODEC and filter).
Figure 2-3: 6-Port CO Module 
						

							2-6DHS General Description
Standard MOH/BGM Module
The standard MOH/BGM Module is installed at the factory and used to interface with one 
external music source via an 1/8 in. phono type connector. This module must be 
removed if the optional module is installed.
Figure 2-4: MOH/BGM Module
Option Module
The Option Module replaces the standard MOH/BGM Module. The Option Module 
contains two DTMF receivers and two Tone Detectors that enable the following features: 
Dial Tone Detection, External Call Forwarding, Direct Inward System Access, Automatic 
Busy Redial and Unsupervised Conference. Interface circuits and hardware connectors 
are provided for SMDR (Station Message Detail Recording), PC Programming, Caller ID, 
Loud Bell Control, External Voice Paging and two music sources. Connectors for SMDR 
and PC Programming are 9-pin RS-232 (serial) connectors. Connectors for Loud Bell 
Control, External Voice Paging, MOH/BGM and BGM2 are 1/8 in. phono type connectors.
Figure 2-5: Option Module 
						

							DHS General Description2-7
Digital Key Telephones
The DHS and DHS-E support three proprietary digital key telephones (Basic, Enhanced 
and Executive). All key telephone models operate on one single twisted pair and provide 
D/A and A/D conversion at the terminal. These key telephones support hot key pad for 
dialing digits at any time.
Basic Key Telephone
The basic key telephone (refer to Figure 2-6) is equipped with a speaker for monitoring 
call progress and receiving call announcements but is not equipped with a microphone 
for hands-free reply. The basic key telephone has 16 buttons, 8 of which are fixed 
function buttons to control settings and primary key telephone call processing 
operations: HOLD, TRANS (Transfer), FEAT (Feature), CLEAR, MUTE, SPKR (Speaker), and 
Volume UP/DN.
Eight buttons are user-programmable feature buttons, that are equipped with dual color 
LED with preassigned default settings for quick power up operation. These buttons are 
arranged in two rows and four columns. Beginning at the top left button they are 
assigned the following default values; CO line 1, CO line 2, CO line 3, CO line 4, CO line 5, 
CO line 6, HF/Tone and Message Waiting.
Figure 2-6: Basic Key Telephone