
DTR-4630
I.R.T. Communications Pty Ltd | www.irtcommunications.com
Page 9 of 17
Revision 02
Optical Connections:
Optical connections are made to the panel adapter mounted on a bracket at the rear of the module. Care must be
taken to provide a clean surface on the optical connectors and in inserting the plug on the external fibre to prevent
damage to the alignment ferrule of the panel adapter. Type of fibre used must be single mode type.
The standard configuration for the DTR-4630 has separate optical connectors for the transmitter and receiver
sections. The transmitter optical output connector is the upper half of the optical connector, whilst the receiver
optical input connector is the lower half.
If the DTR-4630 is fitted with the optional 1300/1550nm wave division multiplexer (WDM), only one common
optical connector is provided with both transmit and receive functions occurring on a single fibre. When operating
the DTR-4630 as a pair with the WDM option fitted, one unit must be fitted with a 1310nm (or 1260-1360nm)
optical transceiver and the other with a 1550nm (or 1520-1600nm) optical transceiver.
Note that for path lengths ≤ 9 dB for APD detectors, or ≤ 3 dB for PIN detectors, an optical attenuator must be
used to avoid over driving the receiver part of the transceiver. For the standard DTR-4630 with no WDM option
fitted, an external optical attenuator is supplied as standard with the unit. For DTR-4630’s fitted with a WDM
device, only the 1550nm version comes equipped with an external optical attenuator as it shares the same fibre
together with the 1310nm version.
Alarm Connections:
The external alarm contact connections are made to the 4 pin phoenix style connector at the bottom of the rear
assembly. On an alarm condition relay contacts go open circuit, that is switch open with respect to ground.
The connections being:
The alarms reported are designated as either Major or Minor and relate to either the transmitter or receiver
sections.
A Major alarm is designated as either a laser fail alarm for the transmitter section; or an optical input to the
receiver section is missing, or the optical signal level is absent.
A Minor alarm is designated as either one or both signal inputs are missing or invalid for the transmitter section; or
the optical input level to the receiver is low, or the receiver outputs are muted implying that the electrical signal is
missing or invalid.
Note that when operating the DTR-4630 as either a transmitter or receiver only, Major and Minor alarms may be
reported due to the nature of electrical or optical inputs not being used. It is not possible to disable the other non
used function alarm conditions.
1
GND.
2
GND.
3
Major Alarm.
4
Minor Alarm.