The ZB-DSSH block (fig. 16921 - 00-00) is intended for protection of track relays of the DSSh-13 types against hindrances of current with a frequency of 50 Hz at power supply of track circuits by current with a frequency of 25 Hz.
The ZB-DSSH block is executed in NSh relay dimensions. On plastic socle there is steel bracket on which establish throttle and board with MBGCh condensers (total capacitor capacity 12 microfarad).
At tension on entrance of the block of 10 V with a frequency of 50 Hz there has to be voltage resonance. At the same time tension on throttle and condensers has to be equal. The difference between tension is allowed no more than 3 Century.
Good quality of the protective block after long work (not less than 2 h) at tension on entrance of 10 V with a frequency of 50 Hz and the ambient temperature of 20 °C has to be not lower than 11, and at top working temperatures from + 60 °C to - 60 °C - not lower than 8.
ZB-DSSH blocks are manufactured for the following operating conditions:
- ambient air temperature from - 60 °C to + 60 °C,
- upper value of relative air humidity 100 at temperature + 25 °C.