Triguard SC300E PDC24 / PAC Chassis Power Supplies (PDC24 / PAC) Issue 3 October 2005 INTRODUCTION PURPOSE Two Power Supply Units (PSUs) provide a dual-redundant source of 5.4Vand 12Vdc onto the backplane for the modules mounted in a SC300E chassis. The PSUs are mounted one above the other in the left hand side of the chassis as shown. Each PSU has a fault warning system and a power sharing system. The power sharing system operates when both PSUs are working.
Triguard SC300E ASSOCIATED DOCUMENTATION Reference Title 008-5097 Chassis User Manual Specification Model PDC24 PAC Nominal input voltage 24Vdc 110/230Vac Auto ranging Input voltage range 20 to 36Vdc 92 to 132Vac or 184 to 264Vac Input frequency range Not applicable 45 to 65Hz Input power 200W 235W Output power 145W 175W Outputs 5.4Vdc @ 18A 5.4Vdc @ 23A 12Vdc @ 4A 12Vdc @ 4A Output hold up time 20 mS 20mS Inrush current 170A, 1.
Triguard SC300E PDC24 / PAC Chassis Power Supplies ENVIRONMENTAL SPECIFICATIONS The maximum ambient temperature measured at the hottest point within the Triguard system shall not be greater than 60 degrees centigrade.
Triguard SC300E TECHNICAL DESCRIPTION PHYSICAL The PSU comprises a front plate mounted at right angles to a chassis plate. All the user controls and indicators are mounted on the front plate as shown in Figure 1-1. The chassis plate supports three main items: • Power supply unit: A self-contained switch-mode power supply unit (SMPS). • Front panel PCB: Contains printed wiring and physical support for the controls and indicators that are viewed and accessed from the front panel.
Triguard SC300E PDC24 / PAC Chassis Power Supplies Figure 2-1 PSU Layout and dimensions PDC24 / PAC October 2005 – Issue 3 5
Triguard SC300E EXTERNAL CONNECTIONS Chassis backplane connector PL3 The chassis backplane connector details are given in Table 2-1. DIN41612 type H15 male connector. SK1 acts as a guide to prealign connector PL3 with its mating socket when the PSU is inserted into its slot. Table 2-1.
Triguard SC300E PDC24 / PAC Chassis Power Supplies Test connector The 8-way 270º DIN socket located on the front panel. The connector pinout details are given in Table 2-2. Table 2-2.
Triguard SC300E THEORY OF OPERATION Main power flow The 5.4V output allows for a drop of about 0.4V across the auctioneering diodes in each module supplied. The output voltage is fed back to the SMPS control circuits via the +ve and -ve sense lines. The SMPS then compensates for any voltage drop along the power supply lines by increasing its output voltage. The rated output voltage is thus present at the load rather than at the PSU output terminals.
Triguard SC300E PDC24 / PAC Chassis Power Supplies SWITCHES AND INDICATORS All user interface is via the front panel (Figure 2-3 ). The following facilities are provided: Table 2-3. Front panel facilities LED Indicator Indication Normal LED (green) Illuminates to indicate normal operation Power Share LED (yellow) Illuminates to indicate that power sharing is in balance. It can extinguish if the other PSU supplies about 1.3A more current. Balance can be adjusted (see Section 3.
Triguard SC300E Figure 2-3 PDC24/PAC Front panel 10 PDC24 / PAC October 2005 – Issue 3
Triguard SC300E PDC24 / PAC Chassis Power Supplies SERVICING SCOPE The PSUs have no field replaceable parts. Faulty units should be returned for repair. CONFIGURATION No configurable links. FIELD FUNCTIONALITY TESTS The 12V supply is not calibrated. Set up the 5V supply as follows. For each test use a digital voltmeter across the relevant pair of pins on the 8-way DIN socket. Output voltage (5V) Measure across pins 6 and 7. The voltage should be 5.4V ±0.01V.
Triguard SC300E Front panel LEDs Check that the green LED (Normal) is on and the red LED (Fault) is off. A fault condition can be due to: • A failure of the ac/dc input supply • An output below 5.1V • An SMPS over temperature condition. Check that the yellow LED (Power Share) is on. It extinguishes when the other PSU is supplying the greater current. If the Power Share LED is extinguished and no fault is indicated on either PSU, there could be an imbalance in output between the two PSUs.
Triguard SC300E PDC24 / PAC Chassis Power Supplies SERVICE SUPPORT SPARE PARTS Spare parts and technical advice can be obtained from your local area office.
