Chapter 9 • Connection and parameterisation User Manual Series F-BO-AFE701) The status LED illuminates green as long as a valid Purging program is set.Fig. 14: Parameterisation of the internal time of the Purging unit9.5.2.2 Automatically synchronising the timeIn addition to manually setting the time, the time of the Purging unit can also be set to 00:00 hoursby means of an external timer. This is done by short-circuiting the line to the fault input (termin-als 3 and 4 of the Purging unit) for a duration of between 50 and 70 seconds; by removing the shortcircuit the internal clock will be set to 00:00.You can realise this, for example, by means of a timer which is programmed in such a way thatit's output closes daily at 23:59 and opens again at 00:00 hours.If the short circuit exists for more than 70 seconds, this will be evaluated as fault! If the short cir-cuit on the fault input exists for less than 50 seconds, this will be indicated by the status LED, butapart from that it will not be evaluated.9.5.3 Setting and displaying the device numberIf several Automatic Purging Units Series F-BO-AFE70 are used in the automatic mode with Pur-ging program, and if they are connected to a common compressed-air system, a staggered operationhelps to avoid overstressing of the compressed-air supply.For this purpose, the Purging units can be programmed with a device number between 0 and 32.The factory setting of the devices is no. 0. By increasing the device number by 1, the Purging pro-cess of the respective Purging unit is delayed by 2 minutes, so that only one Purging unit consumescompressed air at any one time. The maximum possible time delay is 32 x 2 = 64 minutes.At the set start time, the Purging unit with device number 0 will start, 2 minutes later the deviceno. 1 will start, another 2 minutes later the device no. 2 will start, etc.As a prerequisite, of course the time of all Purging units involved must have been set to the sametime.In order to program the device number you have to turn the rotary switch „Purging program“ SW1to position „F“. Apart from that, the device number is displayed and set in the same way as thetime, as explained from page 37 onwards in Chapter 9.5.2.1: „Displaying and manually setting thetime“.The device number is stored in the nonvolatile memory of the Purging unit. Therefore the devicenumber will remain stored indefinitely even if the Purging unit is not being powered.1) The status LED D1 illuminates green as long as a valid Purging program is set.Fig. 15: Parameterisation of the device number of the Purging unitI56-4252-010D200-104-0038