TECO F33 Series, Instruction Manual, Page: 48 / 192

Main Features 45
7.6.8 Checklist And Tips
1. Main Functions
Start by choosing which of the two main functions to use:
- "Alternating MASTER" function
In this case the “Master” pump can be alternated, although this function needs slightly more complicated wiring than the
“Fixed MASTER” function described below. The I/O Board option is necessary.
- "Fixed MASTER" function:
One pump is always the master, only the additional pumps alternate.
Notice that there is a big difference in the wiring of the system between these main functions, so it not possible to switch
between these 2 functions later on. For further information see section 7.6.2, page 41.
2. Number of pumps/drives
If the system consists of 2 or 3 pumps the I/O Board option is not needed. However, this does mean that the following
functions are not then possible:
- "Alternating MASTER" function
- With isolated inputs
With the I/O Board option installed, the maximum number of pumps is:
- 6 pumps if "Alternating MASTER" function is selected. (see section 7.6.3 on page 41)
- 7 pumps if "Fixed MASTER" function is selected. (see section 7.6.2, page 41)
3. Pump size
- "Alternating MASTER" function:
The sizes of the pumps must be equal.
- "Fixed MASTER" function:
The pumps may have different power sizes, but the master pump (F33) must always have the greatest power.
4. Programming the Digital inputs
If the digital inputs are used, the digital input function must be set to Drive feedback.
5. Programming the Relay outputs
After the Pump controller is switched on in menu [391] the number of drives (pumps, fans, etc.) must be set in menu [392]
(Number of Drives). The relays themselves must be set to the function SlavePump1-6 and if Alternate master is used,
MasterPump1-6 as well.
6. Equal Pumps
If all pumps are equal in power size it is likely that the Upper band is much smaller than the Lower band, because the max-
imum pump discharge of the master pump is the same if the pump is connected to the mains (50Hz). This can give a very
narrow hysteresis causing an unstable control area in the flow/pressure. By setting the maximum frequency of the inverter
only slightly above 50Hz it means that the master pump has a slightly bigger pump discharge than the pump on the mains.
Of course caution is essential in order to prevent the master pump running at a higher frequency for a longer period of
time, which in turn prevents the master pump from overloading.
7. Minimum Speed
With pumps and fans it is normal to use a minimum speed, because at lower speed the discharge of the pump or fan will
be low until 30-50% of the nominal speed (depending on size, power, pump properties, etc.). When using a minimum
speed, a much smoother and better control range of the whole system will be achieved.