Database
[{"DeviceType":"A","DeviceStatus":"On"},{"DeviceType":"B","DeviceStatus":"On"},{"DeviceType":"A","DeviceStatus":"Off"},{"DeviceType":"A","DeviceStatus":"On"},{"DeviceType":"A","DeviceStatus":"Off"},{"DeviceType":"A","DeviceStatus":"InRepair"}]
Query
db.collection.aggregate([{$group:{_id:"$DeviceType",DeviceStatusOnCount:{$sum:{$cond:[{$eq:["$DeviceStatus","On"]},1,0]}},DeviceStatusOffCount:{$sum:{$cond:[{$eq:["$DeviceStatus","Off"]},1,0]}},DeviceStatusInRepairCount:{$sum:{$cond:[{$eq:["$DeviceStatus","InRepair"]},1,0]}}}},{$addFields:{DeviceType:"$_id"}},{$project:{_id:0}}])