Signalmont Hradec Králové

Basic electronical products

The Small Supply Equipment for the railway safety appliance

"Small feeding sources for railway securing appliances" - includes a description of all the electrical appliances that are in the production programme of Signal Mont Ltd. Hradec Králové company. There are appliances of the efficiency up to 7,5 kVA and an oscillation of 50 - 75 - 275 Hz, that are determined for the feeding of track circuits, signals, an appliance for a supplement of gate inlays, apt. for generation of oscillation signals for various signal and indication purposes. The appliances are specially constructed to conform to safety standards for securing technology.


The electronic supplies of the serie EZ 1 - 73304
The BZS 1 R 96 - 71981 supply
The battery spare supply BZZ 1 - 71991
The BZP 2 - 71970 9 003 supply
The BZL TP - 37400 9 004 supply
The BZ 1 - VÚD - 73305 9 002 supply
The BZ 1 - UNI - 73305 9 003 supply
The electronic inductor EI - 73306
The safe supply of oscillating signals BZKS 20 - 72845

The article comprises the description of all electronic supplies, that are in the production programme of the Signal Mont Co. Ltd. Hradec Králové. It concerns the supplies designated for supplying railway circuits with power upto 6 kVA and frequency 75 or 275 Hz, the supply of semaphores with power upto 1 kVA (50 Hz) and some special supplies, e. g. supplying the release of block inserts to generate oscillating signals for various signalling and indicating purposes etc. The supplies are specially constructed to fullfil the safety criterions for appliance safety.

The production of supplies for railway safety appliances, especially for supplaying railway circuits has a many years´ tradition in our firm, because it is the successor of former Communication and Security Protection Plants in Hradec Králové.

The beginning of the supplies´ production came in the time when former CSD ( Czechoslovak railway ) started to need the supply of the two-phase railway circuits with a voltage different from the frequency of the mains (i.e. 75 or 275 Hz).

The BZY supply type 1 with the power 1 kVA and frequency 75 Hz was developed as the first product of this type. It is used to feed the mains´ voltage 3 x 380 V/50 Hz. The supply type BZB 1 was developed for feeding the railway circuits not depending on the mains´ voltage as a unit system with the module 0,1 kVA (for feeding the local phase). We reached today´s production range of supplies through following development stages, which are going to be mentioned in more detail later.

Now we are producing two types of supplies for feeding, each of them in a whole range of variations. The supplies´ range EZ 1 serves for a smaller need of power (the feeding of about 8 railway circuits) and the range BZS 1 - R I6 is for feeding bigger stations.

Electronic supplies´ range EZ 1 - 73304 is possible (according to the recquired specification) to be fed either from a DC supply 24 V, resp. 28 V (battery feeding) or from the mains 230 V/50 Hz. They enable to create several variations differing in power, number of phases, output voltage, output frequency and the nature of input voltage. This solution enables to cover the requirements which were provided with totally different types of supplies.

The supply EZ 1 enables railway circuits to work with the signal frequencies 75 Hz or 275 Hz. The output voltage of individual supply phases is of a rectanguar course with the effective value of the fundamental harmonic 220 V and is stabilized with accuracy +/- 10 %. The phase shift between individual outputs is eligible in the range 0° + 180° in steps 15°. They are circuits, but in the mode of a spare supply with input voltage of 21 - 36 V DC and one phase output voltage 220 V/ 50 Hz after completion with sine-course filter.

Individual modifications of the supply EZ 1 exceed the possibility of using this supply in railway safety appliances. The supply enables alternating the function in the so called dependent supply mode, where the synchronous operation of dependent supplies by means of principal supply and synchronous main is guaranteed. It generates the output voltage of the same frequency and phase as the principal supply. The synchronous operation is guaranteed for generating frequencies 75 and 275 Hz.

The indicated assortment is not final and it is possible to extend it more on the request of customers.

The electronic supply is the unit construction created as a tank type ALMES with built-in cassettes of electronic circuits in a way enabling to put together the supply with the requested parameters from individual function modules. The parts of the supply are output transformers (event. output filters) individually placed outside the tank of the supply.

The supply EZ 1 is designed to fulfil the requirements of the railway safety way and to not let the output voltage of the supply go beyond the limited line, and to monitore the frequency of generated output voltage. If the supply works as a dependent supply, the spectral purity of the synchronizing signal on the output of the dependent supply´s safety is also checked ( Especially harmful is the influence of a disturbing signal of an industrial frequency.).

The autonomous frequency exchange is replaced in this case by the frequency depending on the exchange and the key connector is replaced by the socket connecting the synchronizing line.

The supply is provided with the monitoring circuits of the output voltage, whose output can be used to control the external failure relay (by mean of which it is possible to keep the supply in reserve), the central indicator of failure, event. other couplings. It is short-circuit proof on outputs event. against fast changes in loading.

It is possible to switch the EZ 1 supply powerless and switch it off by means of an external switch. This possibility enables to make the scheme of auxiliary controlling circuits in supplying easier, event. to exploit for supply in feeding of impulse railway circuits. It is provided with optical signalisation of all important working states of all functional modulus of supply which enables to rapidly check the supply function and the identification of an event. failure. The efficiency of the supply is higher than 75 %.

During the backup of the main EZ 1 supply´s function by the spare supply, only one set of output transormers is used and the overswitching of output supplies is then made by an overswitching set before these transformers.

The BZS 1 - R 96 - 71981 supply is an electronic converter given for feeding of two phase railway circuits with the operating frequency 275 or 75 Hz. (The output stages of power units are driven by frequency exchange, which allows to gain three-phase shift voltages in 22,5°steps on outputs. It is possible to combine both the phase shift by means of interconnecting frequency exchange and the appropriation of single outputs of local or railway phase.). It is possible to use this supply for coding. It is fed from the mains 3 x 400/230 V - 50 Hz. The nominal max. power is 4 x 1,75 kVA.

The unit construction system is made in such a way that it is possible to feed the railway circuits without interruption when the complementary equipment the so-called battery backup supply BZZ 1 - 71991 is used for the set of BZS 1 - R96 supply. This supply is designed for the cooperation with the main converter of the BZS 1 - R96 supply.

The base of the supply is created by the main convertor, which forms together with the transformer panel the most single variants of the product (in the standing position it takes up 8 floors). The converter (made by the tank with all controlling electronics) then contains 1 to 4 so-called power units at 1,75 kVA each. It´s real number is derived from the supplied railway circuits, event. requested by the whole power. The standard is set that all the time the first one or two power units are used for feeding the local phase and the second or two second ones are used for feeding the railway phase. In this way it is possible to feed max. 47 or 94 railway circuits (see notes for designing the supply BZS 1 - R96). The supply can work with the nominal frequency of 275 or 75 Hz. (The real values of these frequencies are 269,4 Hz +/- 0,1 % and 75,12 Hz +/- 0,1%). Another possiblity is the combined variant (the supply tank contains both frequency exchanges.) E. g. the first two power units work with the frequency 275 Hz (station railway circuit) and the other two with 75 Hz (line railway circuits), event. further combination is possible according to the specific need.

In case the main converter of the interruption of the electrical energy delivery in places where two independent mains are at disposal fails, it is useful to complete the main converter with a spare converter. This is the same construction and it is settled with the same power unit as the main supply. There is always one common part of the BZS 1 - R96 supply -the so-called transformer panel-, which separates the main circuits from the safety ones. It is common for both converters and its function in the system is to automatically overswitch the spare computer, in case the main converter fails ( or the network feeding the main converter gets interrupted ) it will automatically over switch the spare converter. It contains one 1st class safety relay except for the output transformer, which guarantees the safety of the output voltage, if the parameter does not fit.

The spare converter can work as a so-called hot (the consumption cca 40 VA for one power unit) and cold reserve (the whole consumption of the converter is max. 6 VA). In case of the hot reserve it switches over the load after 0,3 sec., in case of the cold reserve it does it in about 4 sec. In both cases it returns to the main converter in about 0,4 sec.

The system with a battery buck-up supply BZZ 1 enables: over-switching totally without any interruption, the functioning of the supply for a certain time without an interruption and the functioning of the supply for a certain time without the presence of the mains´ voltage. This is formed by one tank in a similar way to the tank of the converter BZS 1 - R 96 and it takes up the hight of 4 floors in the standing position. That´s why the complete set of the supply BZS 1 - R 96 with a reserve occupies 13 floors in the standing position including the battery spare supply BZZ 1. So far there is not enough place. It is possible to place the tank BZZ 1 anywhere. For functioning, an accumulator of 24 V DC with a recharger is needed; it is possible to use the existing accumulator for RZZ or to install a new one for this supply. Its dimentioning is stated according to the loading (the number of railway circuits) and the time (more detailed informations may be given by the producer).

The BZS 1 - R 96 supply delivers the rectangular voltage course on the output with 1 harmonic 220 Vef galvanicly separated with the insulating strength 4 kV from the input voltage, from others outputs, and also from the circuit 24 V when the battery reserve BZZ 1 is installed. The outputs are short-circuit-proof, electronic protection in this equipment is taken for granted.

The use of the rectangular voltage enables railway circuits with phase sensitive relays to work in the same way as by sine-course feeding. The construction of supplies is easier, which contributes to higher efficiency and reliability.

For fulfilling the EMC´s requirements the supplies on outputs are equipped with filters, which limit the entering and descending edges and allow to connect the load in the same time with a long cabel (a few km). There is a filter against pulse interference and overvoltage peaks on the input, and the measurement for supressing the back influence to mains is provided (the suppressing of the higher harmonics of the taken current).

The number of supply outputs is stated by the number of power units in the converter. If the population is in four power units when the first two work on local phase and the second two on the railway phase, it is possible to deliver the variant of the BZS 1 - R 96 supply with two outputs at 3,5 kVA. Each of these set-ups are formed by a suitable construction of transformer panel. It is suitable, when we replace an old rotary converter, event. this converter can stay as a reserve. The interconnection is made only by means of four lines and it is not necessary to divide the load into two approximately same groups.

It is possible to practice the BZS 1 - R 96 supply in a synchronous mode. Thus one of them has the function of a guiding one and the other (event. some others) is (are) dependent (they work synchronously i. e. with the same frequency and in the same phase as the guiding supply). The converter of this supply (these supplies) in this case has a dependent frequency exchange (if the spare converter is populated in the same way) and there are more circuits connected to the synchronizing line - separately with the dielectric strength 4 kV.

To have the full picture of all the indicated possibilities of the BZS 1 - R 96 supply it is necessary to introduce the solution with the special frequency exchange (it is used in METRO Ltd.) with two frequencies with an interval cca 10 Hz to choose from. It is used for feeding railway circuits, which must have different frequencies, when the synchronous operation is not used.

The further types of supplies serve for feeding some devices during the failure of the mains. There is the BZP 2 supplies for feeding the electromachine point operating gear, the BZL TP supplies is particularly destined for feeding computer technology (technological computers) and supplies in BZ 1 group for other odd devices.

The supply BZP 2 - 71970 9 003 is the supply of 3 phase ac. voltage, fed from the station battery 24 V DC, destined for feeding 3 phase synchronous machines of electromachine point operating apparatuses. The manner of feeding the machine with a rectangular voltage with a 60° delay in zero was used and the starting of the supply with the contact in powerless state was implicated. Today´s semiconductors enable to design the supply in a very small and light state and with the possibility of a softer start. The power of the supply is designed in order to start up the engine in the clutch set on max strength with the organ locked, with the reserve of about 30 %.

The BZP 2 supply is designed as a tank, which needs the volume of one floor in the universal standing position. On the front side there are the control and indicating elements. After removing the cover the connecting terminal board is accessible.

The battery is constantly connected to the power part of the supply and the device is ready for operation, while the resting taken current is about 80 mA. The self starting is made by means of contact (relay, pressbutton) and during its connection, the voltage on the output is for the machine of the point operating gear. The battery current may raise during operation upto 80 A, and depends on the loading of the machine and on the momentary voltage of the battery. The current shock by starting the synchronous machine is reduced by the mentioned soft start, when the voltage and the frequency get high after switching.

The supply has no center of output voltage (neutral wire) because it is destined only for driving the electromotor of the point operating gear and there the center is not needed. It is provided with an input and an output filter. Except for the electromagnetic compatibility requirement the possibility of connecting long cables, i. e. the ability of the supply to cover the capacity load is solved by means of an output filter. The efficiency of the supply is better than 80 %.

The supply involves circuits, which enable remote control and starting up. It is short circuit-proof and automatically blocked by low or too high battery voltage. The output circuits are galvanicly separated and fulfil safety requirements for dielectric strength 4 kV/50 Hz.

The BZL TP - 37400 9 004 supply is destinated first of all for feeding the computer technology, where the absence of mains´ voltage 230 V/50 Hz is assumed. It can feed others odd devices with it upto the stable power of 400 VA. The supply is constructed to be able to supply the needed power for starting up the device for demagnetization of the screen in a couple of seconds.

The output voltage has a rectangular course with the delay in zero, which is suitable for most of mains´ devices. It does not suit the direct connection of fluorescent lamps with the compensating capacitor.

The battery 24 V DC connection is stable, only through a fuse. On the supply panel there is a common panel socket, comprising the indicator of functioning event. failure modes and an on/off switch (it is possible to place the indicator lamp and the switch outside the supply, in a way to be near to handle and to give a good view of the supply function).

The BZ 1 - VÚD - 73305 9 002 supply is designed as the replacement of rotary converter for feeding the crossing´s safety appliance type VÚD with the output power of 150 VA. On the customer‘s wish one can derive a modification with different parameters from this type with regard to real traffic conditions.

The supply is formed by an own converter, which forms ac. voltage with a rectangular course of 220 V/50 Hz from a battery with a 24 V voltage, output filter and supplementary circuits. The shape of casting uses limited space in the frame of the crossing appliance VÚD after the original rotary converter.

The converter is in a push-pull form with separate excitation, populated in transistors in the output stage and in the exciter.

The output filter is made by resonance circuits LC - in series and parallel. In this way the clearness of the load variation concerning the voltage is guaranteed.

The power is started by built-in relay which is switched on by means of interconnecting suitable clamps. The over current circuit breaker connects up the feeding line 24 V and it serves in the same time as the main switch. The output 220 V AC/50 Hz is protected by a fusible fuse and indicated by a glow-tube.

A bigger change in the loading of the supply during the traffic is not expected, it was possible to choose a simple scheme without stabilization of the output voltage. It is set for the given load with the tap on the output transformer.

The BZ 1 - UNI - 73305 9 003 supply (the universal design). Generally it is possible to use it where the feeding of devices with nominal voltage 220 V AC/50 Hz is not guaranteed and the 150 VA power is satisfactory. A battery with the nominal voltage 24 V DC will be used as the supply. The design is stated for the position on the rack.

It is not possible to connect devices to the supplies which have a big start-up current (the compressor, refrigerator etc.).

The BZ 1 UNI supply is formed by an own converter which creates an ac. Voltage with a rectangular course 220 V AC/50 Hz from the battery with voltage 24 V, an output filter and complementary circuits. The output filter is realized by resonance circuits LC in the same way as in the BZ 1 - VÚD supply. Starting up is the same as with built-in relay and is provided with the fusible fuse 25 A.

As a totally unusual supply in our production assortment there is one, which replaces the classical inductor used by electromechanical safety appliance:

Electronic inductor EI - 73306 is designed as the electronic supply of ac. and pulse dc. voltage with parameters able to replace the mechanical inductor - 11001b which is very exacting in the production.

It is possible to use it if there is a mechanic inductor and it enables moreover to interconnect the electromechanical safety appliance with the relay ones. It is fed from the station battery 24 V DC, event. 12 V DC and there are two types of the product following. It enables to excite up to 3 signal block inserts with the line length of a 300 ohm resistance. The frequency is set during the production on 18 Hz. In reasonable cases it is possible to set a different frequency.

EI corresponds in size with three small-sized relays together. It is destined for feeding from the station battery, but it is possible to feed it from the recharger. In this case it is necessary to provide the smoothe the feeding voltage by a suitable capacitor and follow its size.

Installation into the traffic is made by connecting suitable lines by means of contact. It is possible to use the produced and delivered control buttons EI - 13039 (as a supplement EI) for it. The control button EI is equipped with a bulb on the front panel, signalizing the function EI.

The service is based on pressing the switch-on button feeding the EI circuit for the needed time to release the signal block inserts (3 min. are recommended).

When building the EI into the present appliance it is possible to contact the output from mechanical inductor through the rest contact "The control button EI" which can have then the function of the spare supply.

The Safe supply of vibration signals BZKS 20 - 72845 is a fundamental schematic structural and technological innovation of the electronic encoder EK 1, it has been produced since 1984 in stead of the original electromechanical encoders and in the same time as the innovation of the electronic vibrator EKM - 71945 (it enables slow and fast vibration i. e. 0,9 and 1,8 Hz with safety monitoring on the direct and back bus). In the first place the safe supply of vibration signals is estimated (similar to the mentioned encoders) for the safe generation of vibrating signals 0,9 Hz; 1,8 Hz; 3,6 Hz and signal 5,4 Hz (which is not safely controlled) for subsequent coding of rail circuits for LVZ.

The improved and spread function property of the BZKS 20 supply also enables it for use in other applications of the railway safe technologies, where it wasn´t possible to use the electronic encoder EK 1 or EKM. It is possible by means of the BZKS 20 supply with the variant of the supply of ZIP pulses, e. g. to switch the bulbs of the positive light PZS to contactless by overswitching contact with min. vibration of 40 and warning lights PZS with the 59 vibrations. Both are with safe monitoring of vibration. So far it is necessary to switch more lights of warning devices on than is the max. capacity of switches. The number of switches is spread into variants with extension (72845 5 001...) to double the number (see the enclosure T 1 - The survey of variants). The supply BZKS enables to make power vibration buses 0,9 Hz and 1,8 Hz, after completing with the suitable case of safe monitoring of the signal, indication circuits SZZ (in this case it is offered to use the monitoring Dst/st, which enables the monitoring on the retaining bus) and direct coding of rail circuits (without the use of switches TYS). It is possible to populate the supply BZKS 20 alternatively (according to the real situation) with the board of safe monitoring circuit of max. two vibration buses.

Further possible solution variants of traffic needs can be arranged with the producer.

The mechanical version of the BZKS 20 supply is made by the special profile A1 with intern guiding of populated DPS. On one hand its placement separately e. g. on the rack is enabled, on the other hand assembling it into the 19" frames of electronics.

The BZKS 20 supply is mass-produced with the board of ZI supply of pulses (ZIP), the board of feeder N (mains or battery) and max. with two boards of output switches S - Pos. S 1 and S 2 (by the variant with the extension max. four - Pos. from S 1 to S 4). These can be populated alternatively according to individual demands - dc. switches ac. switches or their combination, thereby each contains always two direct and two indirect switches.

The board of switches Sst (72845 5 300) contains two direct -st (AC) (switch on) and two inverse -sti (switch off) switches of ac. current.

The board of switches Sss (72845 5 400) contains two direct -ss (DC) (switch on) and two inverse -ssi (switch off) switches of dc. current.

In case the only one board of switches is enough (it is populated always in position S1), the interconnecting board PD is always used in position S 2.

The board of safe monitoring circuits D for monitoring max. two vibration buses (Dst,st Dss,ss Dst,ss) may still be populated in the supply. For monitoring vibration feeding of signal circuits there is Dstn control for total control (i. e. the retaining buses too) of slow and fast vibration. The monitoring circuits evaluate through the safe mode in accordance to safe technology demands.The input feeding supplied from the input 1, event. the input 2, vibrates with the coding frequency in the range from 0,9 Hz (slow vibration) to 1,8 Hz (fast vi bration). The presence of vibration input signal is expressed by the generation of "safe" dc. voltage on suitable inputs 1 resp. 2 serves for exciting relay-coils. The 1st class safe - the relay NMŠ 2-4000 is recommended.

The input and output circuits of each detached channel of monitoring circuit are galvanicly separated from eachother and from the internal electronic circuits of the board of monitoring circuits.

The supply is constructed for use in the ambient temperature 25° - 70° C and it fits ZIP in the electromagnetic compatibility by railway safety appliance.

It is possible to feed it by means of voltage 230 V or from a battery 24 V with separate connectors. Their mutual position and connection avoid the faulty use of feeding board.

The description of the function and technical properties

The safety supply of vi bration signals BZKS 20 - 72845 is the unit construction system and in max. construction it is populated with five (by variant with extension max. by seven) boards populated printed connection with various functions.

The board of pulse supply (ZI) 72845 5 200 is fed by DS voltage + 5 Vand 12 V. There are 4 contactless powerless DC switches galvanicly separated from the electronic board circuits populated on the board output. These contactless switches are controlled by pulse signals, which are safely generated by controlling circuits with frequencies 0,9 Hz; 1,8 Hz; 3,6 Hz and 5,4 Hz. The principle of safe generation assures that pulse signals on signal outputs 0,9 Hz; 1,8 Hz; 3,6 Hz; will not be faster in case of a probable failure. But failure in the controlling electronics of the board will cause safe locking the generation of pulse signals on the board outputs. The output, generating the pulse signal 5,4 Hz (green code) is not safely supervised. For SZZ, where the slow and fast vibration is used, the Ds 200 variant is not destined (with the modification of interconnectors) for 5,4 Hz on the output from NS IV but delayed 1,8 Hz (in that way the microclicks of signal bulbs development is avoided).

The board of 72845 5 201 pulse supply (ZIP) application is destined for PZS. It generates the frequency for positive signalization – of a min. 40 vibration and warning devices – of a min. 59 vibration.

The board of switches (direct and inverse switches SP/ SI) is designed in two variants:

DS variant (ss - DC switch Sss 72845 5 400) contains two power contactless switches of dc. Current. Its outputs are in the resting position off; they are set in the on mode by connecting dc operating signal to the input of the switch (the couple of direct switches SP). The other couple of dc power switches on the board (the couple of inverse switches SI) has its outputs in the resting position on; they will by set in the state "off" by connecting the dc operating signal on the input switch. Each single switch has a galvanicly separated operating inputs from the power output circuit and the switches are galvanicly separated from eachother.

AC VARIANT (st - AC switch Sst 72845 5 300) of the board is schematically solved in a similar way with the couple of direct and inverse power switches, but it enables to switch on the ac. current in the range of frequencies 50 Hz - 275 Hz sine or rectangular course. The manner of operating ac. switches through dc. input signal is the same as with the board of dc. signals.

The board of direct and inverse switches both in dc. and ac. variants does not demand the auxiliary dc. feeding voltage for its function.

In the basic variant of the supply BZKS 20 there are populated max. two boards of contactless switches (pos. S 1 and S 2) with four direct and four indirect switches in whole (by the variant with the extension up to 4 boards of switches in positions from S 1 to S 4 in whole with eight direct and eight inverse switches). The boards of dc. and ac. switches may be mutually combined (see the table of variants BZKS 20). The controlled inputs of the couples of direct and inverse switches are connected with eachother in series (identical in the basic case of the couple S 2 and S 2 and in the extension of the couple S 3 and S 4) and they are always in the couple direct/ inverse switch. If the use of only one particular board of S switches is sufficient, then it is populated into position S 2 and the interconnecting board is populated in the S 2 position of the board. Through interconnecting the preselected outputs of pulse ZI supply (outputs B 1 - 0,9 Hz, B 2 - 1,8 Hz, B 3 - 3,6 Hz and B 4 - 5,4 Hz) with the input of the couple (direct and inverse) switches (N 1 - N 4), the outputs of the switches are activated with the on/off switch in the rhythm of the preselected code. It is allowed to feed while the choosing the code if we need all parallel connected inputs of boards from S 1 to S 4 of the contactless switch from one preselected output of the ZI supply.

The board of supervising circuit of vibration buses D is feeded by dc. voltage +12 V and –12 V and it is designed in four variants:
- Dss, ss contains two independent monitoring circuits of the dc. vibrating bus
- Dst, st contains two independent monitoring circuits of the ac. vibrating bus
- Dst, ss with one monitoring circuit of the vibrating bus and the second monitoring circuit of the dc. vibrating bus
- Dstn with three input monitoring circuits for slow and fast buses for feeding the signal circuits including the back one. Every monitoring bus has one resultant relay.

The board of supply N is designated for feeding electronic boards of the supply BZHS 20 and is delivered in two variants:
- for feeding with ac. Voltage 230 V (N230 V). There are dc. stabilized voltage +5 V, +12 V and -12 V towards inner "earth" for disposal.

The input feeding voltage is galvanic separated from the output board voltage.

For feeding with the nominal voltage 23 Vdc (N24V). The same stabilized voltages are for disposal on the outputs of the board as in the previous board. The output feeding voltage is also galvanicly separated from the output voltages of the board.

All products of SIGNAL MONT company Hradec Králové have catalogue lists which give more details about the properties of the product, technical description and notes for usage and it is possible to ask.

Signal Mont, s. r. o.
Kydlinovská 1300
Hradec Králové 2, 500 02