Specifications

GEMINI
2
Traffic Outstation Handbook
667/HB/32600/000 Page 30 Issue 11
2.6.5 The MC35 GPRS Modem
The Siemens MC35 Terminal unit is a GSM modem capable of GPRS transmission.
The MC35 supports GPRS transmission up to 21.4Kbps per time slot.
Interfaces to the unit include an RS232 data port, power and an FME (male) aerial
connector. An integrated SIM card reader is included. A diagnostic LED shows the
current state of the unit.
The MC35 Diagnostic LED is used to indicate the following states.
Operating state
LED
Immediately after power up
On for 2 seconds
Network search
or No SIM card inserted
or No PIN entered
or No GPRS network available
Flashes approx 2 secs on, 2 secs off
Standby GPRS Network
Flashes twice quickly every 4 secs
approx
Data Transfer
Flashes on for approx 1 sec when
data is transferred. (This flash usually
replaces the two quick flashes for the
Standby state above)
2.7 THE POWER SUPPLY UNIT (PSU)
This is a 127mm long, 76.2mm wide and 37mm high OEM unit, which supplies the
system with +13.65V. The Outstation uses a float charged battery held within the
PSU case to provide total system backup in the event of mains’ failure.
2.7.1 The Power Supply Unit (PSU) Features
(a) Wide range of AC input voltage
(b) 3000V isolation from the mains
(c) Can be powered by a 12V to 15V DC input supply. (Future enhancement)
(d) Fitted with a single 12V sealed lead acid battery (see section 7.6.3(a) on page
123)
(e) Automatic switching to the battery support in the event of mains failure to the
system
(f) Automatic recharge on restoration of mains supply to the system
(g) 3 years minimum battery life (also see section 7.4 on page 120)
(h) Zero Cross Over – mains supply voltage timing circuit.
(i) 2 x High Voltage photo-coupled isolated inputs. Normally used for monitoring
the states of the associated controller’s mains and signal supply voltages.
Note: Graphos has a different PSU. See Graphos Product Handbook
667/HB/31200/000 (Section 4.18 – Graphos Gemini CPU) for the PSU
features.