# Voltage supply for FlexSystem

24 V FlexCarrier power

The 24 V power has two operation modes:

- Normal

- Backup.

Normal mode

In normal mode the power comes from a semi-floating 24 VDC power inside the FlexCarrier that is generated from the 3-phase AC. The fuses for the 24VDC is placed inside the FlexCarrier which means that it does not rely on the main circuit breakers placed on the front of the FlexCarrier.

Backup mode

In backup mode the power comes from an external 24V source.

Backup mode is when the 3-phase AC is missing to one or more FlexDrives connected to a FlexCarrier. The tool connected to the FlexDrive will not have any power and cannot be monitored, that is, it will not be visible in the controlling software, for example, ToolsTalk 2. All other communication in the FlexSystem works as normal.

The external power supply must be current limited to 8A, double insulation. It shall be certified according to EN 61010-1 or according to another standard compatible with the requirements in EN 61010-1 (for example EN 60950 or EN 60601).

24V Output

There is a floating 1.8 A, 24 VDC output for external equipment in the front of each FlexCarrier.

Current output with faulty units in daisy chained FlexCarriers

Even if the power supply function are broken in one or more of the FlexCarriers in a daisy chain it will still be possible to connect external equipment to all FlexCarriers in the FlexSystem. For available current see the table below:

No. of 6 slot FlexCarriers | 1 faulty FlexCarrier | 2 faulty FlexCarriers | 3 faulty FlexCarriers
--- | --- | --- | ---
1 FlexCarrier | No Output | No Output | No Output
2 FlexCarriers | 1,1 A | No Output | No Output
3 FlexCarriers | 3,45 A | No Output | No Output
4 FlexCarriers | 5,8 A | 2,2 A | No Output
5 FlexCarriers | 8,15 A | 4,55 A | 1 A
6 FlexCarriers | 10,5 A | 6,9 A | 3,3 A

Example

If one the FlexSystem consists of 2 FlexCarriers and 1 FlexCarrier is broken, the total available max current is 1.1 A. This means that 0.55 A is available from each FlexCarrier if an external equipment is connected to both FlexCarriers.

If one the FlexSystem consists of 6 FlexCarriers and 1 FlexCarrier is broken, the total available max current is 10.5 A. This means that 1.75 A is available from each FlexCarrier if an external equipment is connected to all 6 FlexCarriers. If external equipment is connected to 5 of the FlexCarriers the available current for each external equipment will be 1.8 A.

Backup mode

If an external 24 VDC power supply is connected to the FlexSystem this will distribute differently. A FlexSystem with 1 FlexCarrier can have a load of 1.8 A

Maximum input current can be 8 A. Each FlexCarrier need 1.25 A.

For available current see the table below:

No of FlexCarriers | Total available current | Current available in each port if all ports are used | Max if one port is used
--- | --- | --- | ---
2 | 5.5 A. (8 – 3*1.25). | Both output ports have 1.8 A each | 1.8
3 | 4.25 A. (8 – 3*1.25). | 1.4 in each output port | 1.8
4 | 3 A. (8 – 4*1.25). | 0.75 in each output port | 1.8
5 | 1.75 A. (8 –5*1.25). | 0.35 in each output port | 1.75

Power loss in control cables

It is recommended that the remaining voltage is at least 20 V in the last FlexCarrier in a daisy chain.

The power loss in long control cables limits the usage of long cables.

If running the system in backup mode the length of the IO-bus must be considered.

Power loss in 10 m cable
Load | Remaining voltage
--- | ---
@1A | 23 V
@3A | 22 V
@6A | 20 V
@10A | 18 V