électronique SAFETY MODULE STB 420 FEATURES Checking of 4 power supplies isolated from each other Contrôle de 4 alimentations isolées entre elles Threshold detection for 5V power supply (4.5V) Détection de seuil pour alimentation 5V (4,5V) 4 safety loops for alarms 4 boucles de sécurité pour alarmes Programmable watchdog Levels adjustable from 6V to 220V on power supply check Niveaux ajustables du 6V au 220V sur contrôle alimentation 3 potential-free relay outputs 3 sorties relais libres de potentiel "Fault" display leds Leds de visualisation "défauts" Fitting on DIN RAIL DESCRIPTI The STB 420 module provides the following possibilities : - Checking of 4 DC or AC power supplies isolated from each other ; - Lower limits of the 5V logic for microcomputers (threshold at 4.5V) ; - Checking of 4 safety loops for temperature, ventilation, pressure detection, etc... - Watchdog programmable by switch from a few microseconds to 36 minutes ; - The outputs are potential-free. Le module STB 420 offre les possibilités suivantes : - Contrôle de 4 alimentations, en continu ou alternatif, isolées entre elles ; - Limites inférieures du 5V logique pour les microordinateurs (seuil à 4,5V) ; - Contrôle de 4 boucles de sécurité pour détection de température, ventilation, pression, etc. - Chien de garde programmable par switch de quelques micro-secondes à 36 minutes ; - Les sorties sont libres de potentiel. Small dimensions and easy to integrate into systems or bays (fitting on DIN RAIL), the STB 420 module is an easy-to-use centralized control unit. THE INTERNATIAL CERTIFICATI NETWORK De petites dimensions et facilement intégrable dans les systèmes ou les baies (montage sur RAIL DIN), le STB 420 est une unité de contrôle centralisée simple d emploi. 9, rue Georges Besse - 78330 FTENAY LE FLEURY - FRANCE - tél:(33) 1 30 58 90 09 fax:(33) 1 30 58 21 33 http://www.adas.fr AFAQ ISO 9001 N 1998 / 8803
STB 420 SPECIFICATIS TYPE ISOLATED INPUTS - Number of channels - Type - Level - Isolation MODULE POWER SUPPLY - Number - Level (t = 25 C) SAFETY TERMINAL BLOCK 4 AC or DC Adjustable by channel from 6V to 220V AC Injection resistances on studs HCPL 3700 type photocoupler 1 5V to 24 VDC 5V POWER SUPPLY LEVEL CHECK - Type Adjustable threshold detector (module supplied in 5V supply and 4.5V detection mode) SAFETY LOOP - Number of channels - Fault WATCHDOG - Programming - Range - Level RELAYS - Breaking capacity - Max current - Max voltage PRESENTATI - Dimensions in mm (L x W x H) - Fitting ENVIRMENT - Operating temperature - Storage temperature - Relative humidity 4 By loop opening or threshold By switches From 10µs to 36 minutes TTL reset active in low state TTL watchdog active in low state 30VA 2A 220VAC 115 x 115 x 40 On DIN RAIL 0 C to + 60 C - 10 C to + 70 C 90 % (without condensation) HOW TO ORDER? STB 420 4 98/28
ADAS --- Electronique --- DOCUMENT REVISI SHEET PRODUCT REFERENCE : STB 420 DATE NATURE OF MODIFICATI AUTHOR MARCH 89 MARCH 93 Update of STB 420 documentation Upgrade to Revision B - Edition 2 Documentation update Upgrade to Revision C - Edition 3 Ph. D 1
STB 420 C O N T E N T S A. OPERATI...3 A.1. CHECKING ISOLATED POWER SUPPLIES...3 A.2. SAFETY LOOPS...5 A.3. NOMINAL POWER SUPPLY VALUE FAULT DETECTI...5 A.4. SAFETY FAULT OUTPUT...6 A.5. WATCHDOG...6 B. EQUIPMENT LAYOUT...8 2
A. OPERATI A.1. CHECKING ISOLATED POWER SUPPLIES The STB 420 checks the presence of 4 power supplies isolated from each other and from the terminal block. The switch SW1 validates or not the presence of the power supply involved. E.g. : If there are two power supplies to be checked AL1 and AL2 SW1 4 3 2 1 AL2 AL1 The resistances R1, R3, R5 and R7 have to be adjusted according to the power supply tested. The STB 420 can receive DC or AC signals. The current injection resistances are mounted on studs for ease of channel customization. The STB 420 makes use of the characteristics of the MID 400 products for version A and HCPL 3700 for the other versions. 3
The input structure is as follows : RS RP 1 2 3 4 MID 400 RS RP CF + 1 2 3 4 HCPL 3700 The table below describes the values chosen for the versions available : VERSI A B C D E F NORMAL VIN (V) 5 12 24 48 110 220 RS (KΩ) 2K 1 4.7 10 22 47 CF (µf) NC 4.7 1 1 1 1 Photocouplers MID 400 HCPL 3700 The red led D5 indicates whether there is a power supply fault on the operational channels. The "ISO Supply Fault" relay is then deactivated which corresponds to a fault. It can be noted that when the STB 420 terminal block is not supplied the "ISO Supply Fault" appears. 4
A.2. SAFETY LOOPS The STB 420 terminal block has detection of four safety loops : SECUR1 to SECUR4. The threshold is set by IC 16 (LM 335). If the inputs exceed this threshold, an alarm will occur. E.g. : Ventilation failure. The LM 335 on the fan overheats, the threshold is exceeded, the alarm is triggered. N.B. : For the unused loops ; short-circuit the corresponding inputs. ST3 enables the two groups of two inputs to be "ORed". ST4 enables the watchdog fault relay excitation to be chosen : AB = watchdog BC = safety fault A.3. NOMINAL POWER SUPPLY VALUE FAULT DETECTI The STB 420 module has a level detector performed by the ICL 8211 chip. The resistances R27, R28 and R29 set the triggering threshold. The straps on ST1 enable configuration according to the application. Example 1 : The terminal block is supplied by the 5V of a system and you want to check this : ST1 - fit BC and EF. Example 2 : The terminal block is supplied with + 12V by and you want to check the 5V of a system : ST1 - fit AB - Power supply in + 12V by VAlim - Check the 5V by VControle The STB 420 module is supplied with a 4.5V detection. 5
A.4. SAFETY FAULT OUTPUT The "safety fault" output can be triggered by one of the following three faults : = A malfunction on one of the four safety loops. = Detection of voltage lower than the threshold required on ICL 8211. = Checking the presence of the four isolated power supplies. The red led D6 displays the "ε fault" and the "ε safety faults" relay is then deactivated. A.5. WATCHDOG The STB 420 watchdog operates as follows : = On power up, the circuit is set to the "FAULT" state. The red led is lit (D9). = The first pulse from the system boots the watchdog and lets the oscillator go to 1MHz. = At this moment, the led goes out, the watchdog is booted. The pulses then have to occur with a frequency greater than that displayed on the SW2 switches. = If an anomaly occurs, the watchdog trips. Only a repower-up or a pulse on the watchdog INIT input reboots the system. = Watchdog time : The base oscillator of the STB 420 is at 1 MHz. The triggering time is determined by the "SW2" SWITCH assembly. The combination on SW2 sets the time. 6
COMMENTS : = The signals on "watchdog" and watchdog "INIT" are active at low state. = They are TTL compatible. = The minimum width must be 100 ns and it is the leading edge which is taken into account. The table below illustrates the possible time lags : SW2 8 4 2 1 WD TIME 8 µs 32 µs 128 µs 512 µs 2,048 µs 8,19 ms 32,77 ms 131 ms 512 ms 2,1 s 8,39 s 33,5 s 2mn 14 s 8mn 56 s 36mn 26 s 7
B. EQUIPMENT LAYOUT 8