Rendamax R3456 EVO, Руководство пользователя, Страница: 28 / 72

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Hydraulic connection
Hydraulic resistance
∆T-measurement
∆p-measurement
Water flow data R3400 EVO
Hydraulic resistance
The hydraulic resistance depends on
the flow rate through the boiler and the
boiler type. In the graph the resistance
for a specific flow rate can be found.
The R3500 EVO and R3600 EVO are
able to control a speed controlled pump
via PWM or a 0-10VDC signal. It makes
the flow rate modulate in parallel with
the burner load. The minimum flow
rate, to which the pump is allowed to
modulate with the burner load, is 30%
of the nominal flow rate through the
boiler for R3500 EVO and R3600 EVO
versions.
The flow rate through the boiler can
also be checked by calculation. This
can be done with a ∆T as well as a ∆p
measurement.
∆T-measurement
Check the temperature difference over
the boiler (∆T flow-return) when the
boiler is running on 100% load. An
indication of the actual flow rate can
be found with the following calculation
(see table below for nominal data):
∆p-measurement
Check the pressure difference over the
boiler (∆p flow-return) when the boiler
pump is running (burner on is not re-
quired). The nominal ∆p for each boiler
type can be found in the table below,
actual ∆p must be within:
0.45*Δp
nom
≤ ∆p ≤ 4*∆p
nom.
An indication
of the actual flow rate can be found with
the following calculation (see table be-
low for nominal data):
q
actual
= (∆T
nominal
/ ∆T
measured
) * q
nominal
[ m
3
/h]
q
actual
= √(∆p
measured
/ ∆p
nominal
) * q
nominal
[m
3
/h]
R3400 EVO
R3401
EVO
R3402
EVO
R3403
EVO
R3404
EVO
R3405
EVO
R3406
EVO
R3407
EVO
R3408
EVO
R3409
EVO
R3410
EVO
Nominal flow rate m
3
/h
27,9 31,2 36,5 41,3 46,1 50,9 55,7 63,7 71,6 79,6
∆T at nominal flow rate K 20
∆p at nominal flow rate kPa
46 53 36 43 50 58 91 60 130 165
1,0
10,0
100,0
10,0 100,0
P
re
s
s
u
re
d
ro
p
[k
P
a
]
Flow rate [m³/h]
R3401 EVO
R3402 EVO
R3403 EVO
R3404 EVO
R3405 EVO
R3406 EVO
R3407 EVO
R3408 EVO
R3409 EVO
R3410 EVO
Pres
s
ure
d
rop
[k
Pa
]
R3400 EVO