Unit 12 Control Systems

Date: 2015-10-07; view: 465.

technical sales REP: Well, your first decision is whether to go for cab control or floor control. Let's go quickly through the cab options. Basically cabs make sense where the cranes are travelling at speed, or where the operating conditions make it necessary to protect the operator.

customer: What sort of operating conditions are you talking about7

technical sales rep: Well, extreme heat or extreme cold, dangerous or unpleasant fumes -that sort of thing.

customer: I see and the cab is standard?

technical sales rep: No, there are 4 basic positions. There's the laterally mounted cab — here you can see it at one end of the crane bridge. This position gives good visibility of the load. Then, if you look here, there's the centrally mounted cab — here it is in the centre of the crane bridge. Then there's the crab mounted cab — you can see it here mounted directly over the load — this position is very good for close supervision of the load and finally an independently mobile cab which moves along the crane bridge and so the operator can vary his distance from the load.

customer: I see. And you mentioned a cheaper alternative?

technical sales rep: Yes, that's floor control. Usually this means using a control pendent. Here you can see a mobile control pendent. This means the operator can move close to the load if he wants to guide it manually, or he can operate it at a safe distance. In this picture here, you can see a crab suspended control pendent. In this case, the operator is always close to the load and can guide it manually. We recommend this type for repair and assembly work where positioning is vital. The other extreme is the laterally suspended control pendent — this can be used where direct manual guiding isn't necessary.

customer: Is that it?

technical sales rep: Not quite. Finally there's the remote control option. Either using a stationary control console or a small remote control device. These are extremely useful where the operator can't work in the crane area — for example when the crane is handling dangerous chemicals or when the crane must be controlled from several different points.

customer: I see.

technical sales REP: Anyway, let's go and look at some of the cranes in action.