
16
D
GB
F
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09618-05.2012-DGbFEI
PTC1 PTC2
5|Electrical connection
Terminal box
Fig. 19
ATTENTION!
Terminals 1 - 6 on the trigger
unit MP 10 and terminals PTC
1 and PTC 2 on the compres-
sor terminal board must not
come into contact with mains
voltage. This would destroy the
trigger unit and PTC sensors.
The supply voltage at L1-N
(+/- for DC 24 V version) must
be identical to the voltage at
terminals11,12,14and43.
5.5 Electronic trigger unit MP 10
The compressor motor is tted with cold conductor temperature sensors (PTC) connected to the
electronic trigger unit MP 10 in the terminal box. Readiness to operate is signalled by the H3 LED
(green)afterthepowersupplyisapplied.Inthecaseofexcesstemperatureinthemotorwinding,the
unit switches off the compressor and the H1 LED lights red.
The hot gas side of the compressor can also be protected against overtemperature using a thermal
protection thermostat (accessory). The H2 LED (red) is provided for the protection function.
The unit trips when an overload or inadmissible operating conditions occur. Find and remedy
the cause.
5.6 Connection of the trigger unit MP10
INFO! Connect the trigger unit MP10 in accordance with the circuit dia-
gram. Protect the trigger unit with a delayed-action fuse (F) of max.
4A.Inordertoguaranteetheprotectionfunction,installthetrigger
unitastherstelementinthecontrolpowercircuit.
Temperature monitoring connections:
Motor winding: Terminals 1 - 2
Thermal protection thermostat: Terminals 3 - 4
Restart prevention: Terminals 5 - 6
5.4 Start unloader
To avoid current peaks during the starting phase we recommend using the Bock-ESS soft starting
device (Electronic Soft Start). Refer to "Accessories" for further information.
INFO!
Theunithasarestartpreventiondevice.Afteryouhaverectiedthe
fault,interruptthemainsvoltage.Thisunlockstherestartprevention
device and the LEDs H1 and H2 go out.