Control Cables for Upstream Substation Signals & Tripping
Control Cables for Upstream Substation Signals & Tripping
(OP)
I have been regularly using multiple core 2.5 sq.mm XLPE/LC/PVC/SWA/PVC Control cable for signals & tripping between Upstream and downstream Substation with distance upto 5-6 Kms.
The signals are as,
1. Solkar Pilot Wire for Differential Protection Relay - ANSI NO. 87
2. Inter Trip Send - ANSI NO. 94
3. Inter Trip Receive - ANSI No. 85
4. Upstream Earth Switch Inter lock
5. Upstream Circuit Breaker ON Status
6. Downstream Circuit Breaker OFF Status
However, in one of my recent Projects the distance between Upstream and Downstream Substation is close to 11 Kms.
My question is - Can I still use the same Control Cable ''multiple core 2.5 sq.mm XLPE/LC/PVC/SWA/PVC''.
The signals are as,
1. Solkar Pilot Wire for Differential Protection Relay - ANSI NO. 87
2. Inter Trip Send - ANSI NO. 94
3. Inter Trip Receive - ANSI No. 85
4. Upstream Earth Switch Inter lock
5. Upstream Circuit Breaker ON Status
6. Downstream Circuit Breaker OFF Status
However, in one of my recent Projects the distance between Upstream and Downstream Substation is close to 11 Kms.
My question is - Can I still use the same Control Cable ''multiple core 2.5 sq.mm XLPE/LC/PVC/SWA/PVC''.






RE: Control Cables for Upstream Substation Signals & Tripping
RE: Control Cables for Upstream Substation Signals & Tripping
I will come back to your suggested alternative / preference.
As of now, my concern here is,
Can I use ''multiple core 2.5 sq.mm XLPE/LC/PVC/SWA/PVC'' for a length of close to 11kms for signals / tripping as mentioned above.
Is it workable?
Does it have any disadvantages?
RE: Control Cables for Upstream Substation Signals & Tripping
RE: Control Cables for Upstream Substation Signals & Tripping
You can use voice-frequency over a private telco circuit for signalling, but it's generally not fast enough for protection.
* 'unexpected places': refer to Murphy's Law, and note that Murphy was an optimist!
RE: Control Cables for Upstream Substation Signals & Tripping
RE: Control Cables for Upstream Substation Signals & Tripping
trips, no and no, see ScottyUK post.
Today, rule of thumbs, if it's longer then 500m, use fiber optic.
BTW, SEL2506 a best solution ( IMHO ).
RE: Control Cables for Upstream Substation Signals & Tripping
But for present with multiple core 2.5 sq.mm XLPE/LC/PVC/SWA/PVC,
ss far as voltage drop is concerned, potential free contacts are used.
The voltage required is provided locally at host substation using 110V DC System.
Do you still see any issues? - for both signals and tripping.
RE: Control Cables for Upstream Substation Signals & Tripping
Let us know of your misoperations.
RE: Control Cables for Upstream Substation Signals & Tripping
Keith Cress
kcress - http://www.flaminsystems.com
RE: Control Cables for Upstream Substation Signals & Tripping
To use FO Cable do i need to replace the existing planned multiple core 2.5 sq.mm XLPE/LC/PVC/SWA/PVC WITH FO Cable ONLY or some additional components are required within MV Switchgear Panel or outside it.
Thanks
RE: Control Cables for Upstream Substation Signals & Tripping
please see SEL2506 ( I'm not salesman of SEL :) ).
I was used it in two projects, grate, simple and cheap. 8 inputs, 8 outputs, direct 110V DC connection.
Of course two patch panels for fiber optic, please use 100% redundancy for FO.
RE: Control Cables for Upstream Substation Signals & Tripping
RE: Control Cables for Upstream Substation Signals & Tripping
RE: Control Cables for Upstream Substation Signals & Tripping
Keith Cress
kcress - http://www.flaminsystems.com
RE: Control Cables for Upstream Substation Signals & Tripping
something like to:http://www.industrialnetworking.com/Manufacturers/...
you can use SEL2505, possible installation in LV compartment of MV cubicle
Keith.
I meant only fiber optic wires, that means 4 wires minimum.
RE: Control Cables for Upstream Substation Signals & Tripping
the signals between Upstream and downstream Substation at a distance of 11 kms are as,
1. Solkar Pilot Wire for Differential Protection Relay - ANSI NO. 87
2. Inter Trip Send - ANSI NO. 94
3. Inter Trip Receive - ANSI No. 85
4. Upstream Earth Switch Inter lock
5. Upstream Circuit Breaker ON Status
6. Downstream Circuit Breaker OFF Status
As I understand from above post Fibre Optic cable is the right solution. However, due to some project concerns, we have discussed with the Contractor and are being offered a alternative solution to go for SCREENED XLPE/PVC/SWA/PVC control cable of 20 C (10 pair)
Kindly confirm if it is a workable solution.
RE: Control Cables for Upstream Substation Signals & Tripping
RE: Control Cables for Upstream Substation Signals & Tripping
RE: Control Cables for Upstream Substation Signals & Tripping
You can do intertrip send/receive over a pilot using something like an Areva GCM05 intertrip send/receive relay.
I wouldn't recommend doing any interlocking over a pilot. If you do, then you should at least build in safeguards against stuck contacts or open circuits for example by making it two bit, using changeover switches. eg 1-0 and 0-1 are valid, 0-0 or 1-1 indeterminate (lock out)
Regards
Marmite
http://files.engineering.com/getfile.aspx?folder=4...
RE: Control Cables for Upstream Substation Signals & Tripping
RE: Control Cables for Upstream Substation Signals & Tripping
I have an old Areva price guide from 2007 which lists them, and I had a recollection that we were using them in the DNO I worked for in the UK upto 2012, but I may be mistaken. Siemens and others still do surge proof DC intertripping relays though.
Regards
Marmite
RE: Control Cables for Upstream Substation Signals & Tripping
I have obtained information from Siemens Catalogue that is quite useful,
Solkor R & Solkor Rf Pilot Wire Differential Protection Relay (ANSI NO. 87) is suitable for application on a single pair of pilots with loop resistance up to 2000ohms to protect 2 ended feeder circuits up to 20km in length. Two compatible relays are used as a pair with one relay connected to current transformers at each end of the feeder respectively. The Solkor R/Rf relays do not require an auxiliary DC supply.
The Solkor R/Rf relay has an insulation level of 5kV between pilot connections and the local ground to withstand voltages induced on the pilot cable due to coupling with the fault current and to withstand differential ground voltages caused by the flow of fault current. Experience has shown that 5kV insulation is usually adequate for most distribution feeders.
For higher voltage systems where feeders may be longer and fault levels higher, an additional external isolation transformer is available for use with the relay in Rf mode to increase the voltage withstand to 15kV.
RE: Control Cables for Upstream Substation Signals & Tripping