How much is the monthly salary of Shanghai subway maintenance electrician?

The subway electrician is different from the service staff in the station. Electricians should be assigned to Party B. Generally, electricians in the real subway don't work, but manage. The work is subcontracted to the subordinate units of the subway company. The pay is different. The salary is not that high. The electrician inside is very hard. They all work at night. They just changed the lights of the hall platform and the subway tunnel. The salary is about 3000-5300. It's also five insurances and one gold.