Maximum demand, Please explain.
#17
Just Joined
Joined: Dec 2008
Posts: 23
Re: Maximum demand, Please explain.
19 lig point 3amps
6 10 a double skt outlt
16 10a singl skt outlt 15 amps
3 strip heater 1000 watt
1 15amps skt outlet 10 amps
1 20amps skt outlet 15amps
3 exhaust fans 2amps
1 12.4 kw range 27 amps
1 4.6kw instant water heater 6.66amps
4 500watt tennis light 6.50amps
total 85.16 amps
6 10 a double skt outlt
16 10a singl skt outlt 15 amps
3 strip heater 1000 watt
1 15amps skt outlet 10 amps
1 20amps skt outlet 15amps
3 exhaust fans 2amps
1 12.4 kw range 27 amps
1 4.6kw instant water heater 6.66amps
4 500watt tennis light 6.50amps
total 85.16 amps
#19
Just Joined
Joined: Dec 2008
Posts: 23
Re: Maximum demand, Please explain.
old one was mistyped mate.
#20
Re: Maximum demand, Please explain.
Ok have been working through the next few shets of MD. Will put up these sheet by sheet and lets see if I'm right or if you have the same answers. Ok.
Q2 Same category.
Determine the maximum demand of a single phase 240V domestic installation.
28 Lighting points 3A+2a = 5A
8m Lighting track 8 x 2A = 16A
13 10A single socket outlets
+
9 10A double socket outlets
+
2 50W exhaust fans
+
1 1200Watts strip heaters = 13+9+2+1=25points so 10A + 5A = 15A
1 14.5KW range 14500/230 = 63 x 05 = 31.5A
1 3.4kW storage H.W.S. 3400/230 = 14.8A
1 3.0kW clothes drier N/A
Total = 82.3A
Right or wrong?
Q2 Same category.
Determine the maximum demand of a single phase 240V domestic installation.
28 Lighting points 3A+2a = 5A
8m Lighting track 8 x 2A = 16A
13 10A single socket outlets
+
9 10A double socket outlets
+
2 50W exhaust fans
+
1 1200Watts strip heaters = 13+9+2+1=25points so 10A + 5A = 15A
1 14.5KW range 14500/230 = 63 x 05 = 31.5A
1 3.4kW storage H.W.S. 3400/230 = 14.8A
1 3.0kW clothes drier N/A
Total = 82.3A
Right or wrong?
#21
Just Joined
Joined: Dec 2008
Posts: 23
Re: Maximum demand, Please explain.
exactly same answer,Thanx
#22
Re: Maximum demand, Please explain.
Question 3
Determine the maximum demand of the heaviest loaded phase in a domesticv electrical instalation having the following load-
21 Lighting points 3 + 2 = 5A
28 10A single socket outlets
+
8 10A socket outlets = 10A + 5A = 15A
1 range(2 hotplates 6kW each and 6.8kW oven) 18800/230=81.73x0.5=40.86A
1 air conditioner- (single phase 4.8kW) 4500/230 = 19.56 x 0.75= 14.67A
1 clothes dryer - ( single phase 4.8kW) N/A
1 washing machine - ( single phase self heating - 3.2kW) N/A
1 3phase instantaneous water heater (5.3kW per phase) 5300/230 = 23 x 0.333= 7.67A per phase
1 3 phase motor rated at 7.5A per phase = 7.5A per phase
Total 90.7A
Right or wrong?
Determine the maximum demand of the heaviest loaded phase in a domesticv electrical instalation having the following load-
21 Lighting points 3 + 2 = 5A
28 10A single socket outlets
+
8 10A socket outlets = 10A + 5A = 15A
1 range(2 hotplates 6kW each and 6.8kW oven) 18800/230=81.73x0.5=40.86A
1 air conditioner- (single phase 4.8kW) 4500/230 = 19.56 x 0.75= 14.67A
1 clothes dryer - ( single phase 4.8kW) N/A
1 washing machine - ( single phase self heating - 3.2kW) N/A
1 3phase instantaneous water heater (5.3kW per phase) 5300/230 = 23 x 0.333= 7.67A per phase
1 3 phase motor rated at 7.5A per phase = 7.5A per phase
Total 90.7A
Right or wrong?
#23
Just Joined
Joined: Jun 2010
Posts: 25
Re: Maximum demand, Please explain.
Ok have been working through the next few shets of MD. Will put up these sheet by sheet and lets see if I'm right or if you have the same answers. Ok.
Q2 Same category.
Determine the maximum demand of a single phase 240V domestic installation.
28 Lighting points 3A+2a = 5A
8m Lighting track 8 x 2A = 16A
13 10A single socket outlets
+
9 10A double socket outlets
+
2 50W exhaust fans
+
1 1200Watts strip heaters = 13+9+2+1=25points so 10A + 5A = 15A
1 14.5KW range 14500/230 = 63 x 05 = 31.5A
1 3.4kW storage H.W.S. 3400/230 = 14.8A
1 3.0kW clothes drier N/A
Total = 82.3A
Right or wrong?
Q2 Same category.
Determine the maximum demand of a single phase 240V domestic installation.
28 Lighting points 3A+2a = 5A
8m Lighting track 8 x 2A = 16A
13 10A single socket outlets
+
9 10A double socket outlets
+
2 50W exhaust fans
+
1 1200Watts strip heaters = 13+9+2+1=25points so 10A + 5A = 15A
1 14.5KW range 14500/230 = 63 x 05 = 31.5A
1 3.4kW storage H.W.S. 3400/230 = 14.8A
1 3.0kW clothes drier N/A
Total = 82.3A
Right or wrong?
28 Lighting points 3A+2a = 5A
8m Lighting track 8 x 2A = 16A
2 50W exhaust fans = 2
ie total points is 28+ 16 + 2 = 46points
3A+2A+2A = 7A
see egin reg C2.3.2.1 load group A(1)
7A+15A+31.52A+14.78A
Total 68.3Amps
Please let me know if this correct.
#24
Re: Maximum demand, Please explain.
For question 2 Max Demand I have got, total 68.3.
28 Lighting points 3A+2a = 5A
8m Lighting track 8 x 2A = 16A
2 50W exhaust fans = 2
ie total points is 28+ 16 + 2 = 46points
3A+2A+2A = 7A
see egin reg C2.3.2.1 load group A(1)
7A+15A+31.52A+14.78A
Total 68.3Amps
Please let me know if this correct.
28 Lighting points 3A+2a = 5A
8m Lighting track 8 x 2A = 16A
2 50W exhaust fans = 2
ie total points is 28+ 16 + 2 = 46points
3A+2A+2A = 7A
see egin reg C2.3.2.1 load group A(1)
7A+15A+31.52A+14.78A
Total 68.3Amps
Please let me know if this correct.
The 16 for the track is not points but amps.
Last edited by Jockstar; Jun 21st 2010 at 11:19 am.
#25
Just Joined
Joined: Jun 2010
Posts: 25
Re: Maximum demand, Please explain.
Please read note d on pg 358 for lighting
#26
Just Joined
Joined: Jun 2010
Posts: 25
Re: Maximum demand, Please explain.
Also note in the question the voltage 240 is used.
for lighting track read d pg 358,
2 points per metre of track
ie
8 x 2 = 16 points
final answer [B]66.41 Amps[/B].
please check, I already check with one of my mate same answer as mine.
for lighting track read d pg 358,
2 points per metre of track
ie
8 x 2 = 16 points
final answer [B]66.41 Amps[/B].
please check, I already check with one of my mate same answer as mine.
#27
Just Joined
Joined: Dec 2008
Posts: 23
Re: Maximum demand, Please explain.
Thanx for correcting us askar.yea i hve also chkd again u r right.
#28
Re: Maximum demand, Please explain.
Determine the maximum demand of a single phase 240V domestic installation.
28 Lighting points
+
8m Lighting track + 2 50W exhaust fans = 28+16+2= 46 points. Which is 3+2+2=7A
13 10A single socket outlets
+
9 10A double socket outlets + 1 1200 watts strip heaters = 13+9+1= 23 points so that would be 10+5=15A
2 50W exhaust fans
1 1200Watts strip heaters
1 14.5KW range 14500/240 = 60.41 x 0.5 = 30.2A
1 3.4kW storage H.W.S. 3400/240 = 14.16A
1 3.0kW clothes drier N/A
Total = 66.36A
This is what i get after revising the above. Just wondering where you get the extra 0.5A from?
28 Lighting points
+
8m Lighting track + 2 50W exhaust fans = 28+16+2= 46 points. Which is 3+2+2=7A
13 10A single socket outlets
+
9 10A double socket outlets + 1 1200 watts strip heaters = 13+9+1= 23 points so that would be 10+5=15A
2 50W exhaust fans
1 1200Watts strip heaters
1 14.5KW range 14500/240 = 60.41 x 0.5 = 30.2A
1 3.4kW storage H.W.S. 3400/240 = 14.16A
1 3.0kW clothes drier N/A
Total = 66.36A
This is what i get after revising the above. Just wondering where you get the extra 0.5A from?
#29
Just Joined
Joined: Jun 2010
Posts: 25
Re: Maximum demand, Please explain.
Yes your answer is correct.
#30
Re: Maximum demand, Please explain.
Question 3
Determine the maximum demand of the heaviest loaded phase in a domesticv electrical instalation having the following load-
21 Lighting points 3 + 2 = 5A
28 10A single socket outlets
+
8 10A socket outlets = 10A + 5A = 15A
1 range(2 hotplates 6kW each and 6.8kW oven) 18800/230=81.73x0.5=40.86A
1 air conditioner- (single phase 4.8kW) 4500/230 = 19.56 x 0.75= 14.67A
1 clothes dryer - ( single phase 4.8kW) N/A
1 washing machine - ( single phase self heating - 3.2kW) N/A
1 3phase instantaneous water heater (5.3kW per phase) 5300/230 = 23 x 0.333= 7.67A per phase
1 3 phase motor rated at 7.5A per phase = 7.5A per phase
Total 90.7A
Right or wrong?
Determine the maximum demand of the heaviest loaded phase in a domesticv electrical instalation having the following load-
21 Lighting points 3 + 2 = 5A
28 10A single socket outlets
+
8 10A socket outlets = 10A + 5A = 15A
1 range(2 hotplates 6kW each and 6.8kW oven) 18800/230=81.73x0.5=40.86A
1 air conditioner- (single phase 4.8kW) 4500/230 = 19.56 x 0.75= 14.67A
1 clothes dryer - ( single phase 4.8kW) N/A
1 washing machine - ( single phase self heating - 3.2kW) N/A
1 3phase instantaneous water heater (5.3kW per phase) 5300/230 = 23 x 0.333= 7.67A per phase
1 3 phase motor rated at 7.5A per phase = 7.5A per phase
Total 90.7A
Right or wrong?
What about this one?