Nederman NCF Series Instruction Manual

NCF
13
EN
2.5 Operang speed risks
CAUTION! Risk of equipment damage.
• Do not exceed the maximum rotaon speed indicated by Nederman.
• Do not use ON-OFF operang cycles unless expressly approved by Nederman.
• Do not subject the fan to thermal gradients greater than 3°C/minute.
• A condion of overspeed, even for a limited me, may cause irreversible damage and
create situaons of extreme risk hazards. The maximum speeds indicated by Nederman
must never be exceeded.
• The manufacturer must always be contacted in the case of use of a supply frequency
other than the original design frequency. Do not proceed unl authorized.
• In the case of fan operaon with a variable speed cycle of less than 30 minutes, this cycle
must be submied to approval by the Nederman Technical Oce, which will give its
approval and nofy the consequent reducon of maintenance intervals and the fan life
span.
• Inverng the fan rotaon direcon or starng it with the impeller turning in the opposite
direcon may cause breakage of the blades and/or the impeller hub, with the risk of
ejecon of metal parts.
• Resonance phenomena at low frequencies may cause damage to the structure.
Operang speeds greater than those envisaged by the fan design can create condions of
risk due to the reducon of the operave life span of moving parts.
In case of faults or malfuncons, overspeed condions may be created due to:
• Errors in the control logic system
• Short circuits on monitoring components
• Driver or inverter malfuncons
• Mechanical breakage of components, and in parcular on encoder
During normal operaon, condions of overspeed aributable to the drive system or motor
may occur, in parcular if the fan is supplied “with sha only” or with motor “without drive
system”.
The use of a supply frequency dierent from the original design frequency aects all fan
characteriscs. The modicaon of condions of use requires a complete revision of the
technical informaon sheet of the fan.
In the case of use at varying fan speeds or with frequent starng and stopping during
operaon, rotang organs are subject to mechanical stresses that may aect their
operave life span.
If the rotaon direcon of a fan must be inverted, or if it must be restarted, this must be
done only when the impeller is in the rest posion (total standsll).
Operaon at a speed signicantly lower than up to 40% of nominal speed (unless otherwise
specied by Nederman) may aect the cooling of the motor and bearings, with possible
malfuncons due to higher temperatures. For electrical components, the user and installer
are advised to provide adequate protecon for the drive system or motor, with the use of
heat detecon capsules if possible, and also using a servo-venlated motor if necessary.
Resonance phenomena in the structure must be avoided. These may emerge at specic
rotaon speeds, and may cause damage to the structure.

Nederman NCF Series Specifications

General

Brand	Nederman
Model	NCF Series
Category	Fan
Language	English